fix(tui): move agent cycling to shift-tab

Co-authored-by: Dax Raad <d@ironbay.co>

bun.lock

@@ -900,6 +900,9 @@
       "version": "1.17.13",
       "dependencies": {
         "@fontsource/commit-mono": "5.2.5",
+        "@fontsource/noto-sans-math": "5.2.5",
+        "@fontsource/noto-sans-symbols": "5.2.5",
+        "@fontsource/noto-sans-symbols-2": "5.2.5",
         "@napi-rs/canvas": "1.0.2",
         "@opencode-ai/ai": "workspace:*",
         "@opencode-ai/core": "workspace:*",
@@ -1795,6 +1798,12 @@
 
     "@fontsource/inter": ["@fontsource/inter@5.2.8", "", {}, "sha512-P6r5WnJoKiNVV+zvW2xM13gNdFhAEpQ9dQJHt3naLvfg+LkF2ldgSLiF4T41lf1SQCM9QmkqPTn4TH568IRagg=="],
 
+    "@fontsource/noto-sans-math": ["@fontsource/noto-sans-math@5.2.5", "", {}, "sha512-1bxEvVlF51Vfgpju32mRZzI/CHvsfqjXjI2+sAuEyHYvXABUAIyj+93sCO3QZIoMG5drWyrzgoCqRQRaL6wQ8Q=="],
+
+    "@fontsource/noto-sans-symbols": ["@fontsource/noto-sans-symbols@5.2.5", "", {}, "sha512-mxoIRstsmZpZFzd/SRWiD+l6T7TGhpgCrGs7TEnnuGSQIfjVMrQT9Zej2enh9pkfmPNAFyeaGJkHkszJ1hH++w=="],
+
+    "@fontsource/noto-sans-symbols-2": ["@fontsource/noto-sans-symbols-2@5.2.5", "", {}, "sha512-F4O9WLifwoZS1quNzY1ebjMNo2cQPe/UP68Dmud0ONi2lOxaR6xp6fFPO2gG17MI7DwAnfMyQFl64A2tAd28hg=="],
+
     "@fuma-translate/react": ["@fuma-translate/react@1.0.2", "", { "peerDependencies": { "@types/react": "*", "react": "^19.2.0", "react-dom": "^19.2.0" }, "optionalPeers": ["@types/react"] }, "sha512-uOiOtBx3nRXR8Nu1GzBf1tApgF1FErDBTHxRIAQeyQdyOoZbrNRN6H4kDCWObY4qyGeGbHydG0DHzgeUgFDMIw=="],
 
     "@fumadocs/tailwind": ["@fumadocs/tailwind@0.1.0", "", { "peerDependencies": { "tailwindcss": "^4.0.0" }, "optionalPeers": ["tailwindcss"] }, "sha512-nF/DCAwOR21HZ4AkjIOv3Iqwyqywzb6pdyeMcoa+aZzirXj5ntvNZbe3jJ0v3ehhtrRfYYeXBezvjn8ZmV+fuQ=="],

packages/ai/STATUS.md

@@ -1,6 +1,6 @@
 # LLM Provider Parity Status
 
-Last reviewed: 2026-07-16
+Last reviewed: 2026-07-17
 
 This file tracks the gap between the native `@opencode-ai/ai` package and the AI SDK provider packages that opencode still depends on for many catalog/runtime paths.
 
@@ -20,7 +20,7 @@ This file tracks the gap between the native `@opencode-ai/ai` package and the AI
 | OpenAI Responses WebSocket         | `src/protocols/openai-responses.ts`, `src/route/transport/websocket.ts`                        | Present as `OpenAI.responsesWebSocket(...)`.                                                                                                                             | Runner/catalog support explicitly must not downgrade WebSocket routes; broader runtime selection is not complete.                                                                                                                                         |
 | OpenAI-compatible Chat             | `src/protocols/openai-compatible-chat.ts`, `src/providers/openai-compatible.ts`                | Usable for generic Chat and several profiles: Baseten, Cerebras, DeepInfra, DeepSeek, Fireworks, Groq, TogetherAI.                                                       | Family quirks are mostly endpoint defaults, not full typed behavior.                                                                                                                                                                                      |
 | OpenAI-compatible Responses        | `src/protocols/openai-compatible-responses.ts`, `src/providers/openai-compatible-responses.ts` | Usable for deployments that implement the OpenAI Responses wire protocol.                                                                                                | No named family profiles or recorded deployment coverage yet.                                                                                                                                                                                             |
-| Anthropic-compatible Messages      | `src/protocols/anthropic-messages.ts`, `src/providers/anthropic-compatible.ts`                 | Usable for deployments that implement the Anthropic Messages wire protocol. Named Anthropic composes this base.                                                          | No named compatible family profiles or recorded deployment coverage yet.                                                                                                                                                                                  |
+| Anthropic-compatible Messages      | `src/protocols/anthropic-messages.ts`, `src/providers/anthropic-compatible.ts`                 | Usable for deployments that implement the Anthropic Messages wire protocol. Named Anthropic composes this base; MiniMax M3 has recorded text and tool-loop coverage.       | No named compatible family profiles yet.                                                                                                                                                                                                                  |
 | Anthropic Messages                 | `src/protocols/anthropic-messages.ts`, `src/providers/anthropic.ts`                            | Usable. Supports tools, thinking, cache control, images, server-hosted tool events, and usage.                                                                           | Provider option surface is small. Beta/header handling, metadata, and newer Messages fields need a typed parity pass.                                                                                                                                     |
 | Gemini Developer API               | `src/protocols/gemini.ts`, `src/providers/google.ts`                                           | Usable for Google API key flow. Supports text, images, tools, thinking signatures, and cache usage.                                                                      | This is not Vertex. Typed provider options are narrow; many Gemini request fields currently require raw `http.body` overlays.                                                                                                                             |
 | Vertex Gemini                      | `src/protocols/gemini.ts`, `src/providers/google-vertex.ts`                                    | Usable through API-key express mode, explicit OAuth tokens, or ADC with project/location endpoint derivation, including tuned `endpoints/...` deployments.               | Core runner/catalog mapping and recorded provider coverage are missing.                                                                                                                                                                                   |

packages/ai/script/setup-recording-env.ts

@@ -161,6 +161,18 @@ const PROVIDERS: ReadonlyArray<Provider> = [
     vars: [{ name: "TOGETHER_AI_API_KEY" }],
     validate: (env) => validateBearer("https://api.together.xyz/v1/models", Redacted.make(env.TOGETHER_AI_API_KEY)),
   },
+  {
+    id: "minimax",
+    label: "MiniMax",
+    tier: "compatible",
+    note: "Anthropic-compatible Messages text/tool recorded tests",
+    vars: [{ name: "MINIMAX_API_KEY" }],
+    validate: (env) =>
+      HttpClientRequest.get("https://api.minimax.io/anthropic/v1/models").pipe(
+        HttpClientRequest.setHeader("x-api-key", Redacted.value(Redacted.make(env.MINIMAX_API_KEY))),
+        executeRequest,
+      ),
+  },
   {
     id: "mistral",
     label: "Mistral",

packages/ai/src/protocols/anthropic-messages.ts

@@ -703,7 +703,14 @@ const onContentBlockStart = (state: ParserState, event: AnthropicEvent): StepRes
           providerExecuted: block.type === "server_tool_use",
         }),
       },
-      [...events, LLMEvent.toolInputStart({ id: block.id ?? String(event.index), name: block.name ?? "" })],
+      [
+        ...events,
+        LLMEvent.toolInputStart({
+          id: block.id ?? String(event.index),
+          name: block.name ?? "",
+          providerExecuted: block.type === "server_tool_use" ? true : undefined,
+        }),
+      ],
     ]
   }
 

packages/ai/src/protocols/bedrock-converse.ts

@@ -561,7 +561,9 @@ const step = (state: ParserState, event: BedrockEvent) =>
       return [
         {
           ...state,
-          hasToolCalls: resultEvents.some(LLMEvent.is.toolCall) ? true : state.hasToolCalls,
+          hasToolCalls:
+            resultEvents.some((event) => LLMEvent.is.toolCall(event) || LLMEvent.is.toolInputError(event)) ||
+            state.hasToolCalls,
           lifecycle,
           tools: result.tools,
           reasoningSignatures: Object.fromEntries(

packages/ai/src/protocols/openai-chat.ts

@@ -75,6 +75,8 @@ const OpenAIChatMessage = Schema.Union([
     content: Schema.NullOr(Schema.String),
     tool_calls: optionalArray(OpenAIChatAssistantToolCall),
     reasoning_content: Schema.optional(Schema.String),
+    reasoning: Schema.optional(Schema.String),
+    reasoning_text: Schema.optional(Schema.String),
   }),
   Schema.Struct({ role: Schema.Literal("tool"), tool_call_id: Schema.String, content: Schema.String }),
 ]).pipe(Schema.toTaggedUnion("role"))
@@ -145,6 +147,8 @@ type OpenAIChatToolCallDelta = Schema.Schema.Type<typeof OpenAIChatToolCallDelta
 const OpenAIChatDelta = Schema.Struct({
   content: optionalNull(Schema.String),
   reasoning_content: optionalNull(Schema.String),
+  reasoning: optionalNull(Schema.String),
+  reasoning_text: optionalNull(Schema.String),
   tool_calls: optionalNull(Schema.Array(OpenAIChatToolCallDelta)),
 })
 
@@ -166,6 +170,7 @@ export interface ParserState {
   readonly usage?: Usage
   readonly finishReason?: FinishReason
   readonly lifecycle: Lifecycle.State
+  readonly reasoningField?: "reasoning" | "reasoning_content" | "reasoning_text"
 }
 
 // =============================================================================
@@ -208,6 +213,12 @@ const lowerMedia = Effect.fn("OpenAIChat.lowerMedia")(function* (part: MediaPart
 const openAICompatibleReasoningContent = (native: unknown) =>
   isRecord(native) && typeof native.reasoning_content === "string" ? native.reasoning_content : undefined
 
+const reasoningField = (part: ReasoningPart) => {
+  const field = part.providerMetadata?.openai?.reasoningField
+  if (field === "reasoning" || field === "reasoning_content" || field === "reasoning_text") return field
+  return "reasoning_content"
+}
+
 const lowerUserMessage = Effect.fn("OpenAIChat.lowerUserMessage")(function* (message: OpenAIChatRequestMessage) {
   const content: Array<Schema.Schema.Type<typeof OpenAIChatUserContent>> = []
   for (const part of message.content) {
@@ -248,14 +259,20 @@ const lowerAssistantMessage = Effect.fn("OpenAIChat.lowerAssistantMessage")(func
       continue
     }
   }
+  const text = reasoning.map((part) => part.text).join("")
+  const field = reasoning[0] ? reasoningField(reasoning[0]) : "reasoning_content"
   return {
     role: "assistant" as const,
     content: content.length === 0 ? null : ProviderShared.joinText(content),
     tool_calls: toolCalls.length === 0 ? undefined : toolCalls,
     reasoning_content:
-      reasoning.length > 0
-        ? reasoning.map((part) => part.text).join("")
-        : openAICompatibleReasoningContent(message.native?.openaiCompatible),
+      reasoning.length === 0
+        ? openAICompatibleReasoningContent(message.native?.openaiCompatible)
+        : field === "reasoning_content"
+          ? text
+          : undefined,
+    reasoning: reasoning.length > 0 && field === "reasoning" ? text : undefined,
+    reasoning_text: reasoning.length > 0 && field === "reasoning_text" ? text : undefined,
   }
 })
 
@@ -400,6 +417,12 @@ const mapUsage = (usage: OpenAIChatEvent["usage"]): Usage | undefined => {
   })
 }
 
+const reasoningDelta = (delta: Schema.Schema.Type<typeof OpenAIChatDelta> | null | undefined) => {
+  if (delta?.reasoning_content) return { field: "reasoning_content", text: delta.reasoning_content } as const
+  if (delta?.reasoning) return { field: "reasoning", text: delta.reasoning } as const
+  if (delta?.reasoning_text) return { field: "reasoning_text", text: delta.reasoning_text } as const
+}
+
 const step = (state: ParserState, event: OpenAIChatEvent) =>
   Effect.gen(function* () {
     const events: LLMEvent[] = []
@@ -412,8 +435,12 @@ const step = (state: ParserState, event: OpenAIChatEvent) =>
 
     let lifecycle = state.lifecycle
 
-    if (delta?.reasoning_content)
-      lifecycle = Lifecycle.reasoningDelta(lifecycle, events, "reasoning-0", delta.reasoning_content)
+    const reasoning = reasoningDelta(delta)
+    const reasoningField = state.reasoningField ?? reasoning?.field
+    if (reasoning)
+      lifecycle = Lifecycle.reasoningDelta(lifecycle, events, "reasoning-0", reasoning.text, {
+        openai: { reasoningField: reasoningField ?? reasoning.field },
+      })
 
     if (delta?.content) {
       lifecycle = Lifecycle.reasoningEnd(lifecycle, events, "reasoning-0")
@@ -437,7 +464,7 @@ const step = (state: ParserState, event: OpenAIChatEvent) =>
     }
 
     // Finalize accumulated tool inputs eagerly when finish_reason arrives so
-    // JSON parse failures fail the stream at the boundary rather than at halt.
+    // valid calls and malformed local calls settle independently.
     const finished =
       finishReason !== undefined && state.finishReason === undefined && Object.keys(tools).length > 0
         ? yield* ToolStream.finishAll(ADAPTER, tools)
@@ -450,6 +477,7 @@ const step = (state: ParserState, event: OpenAIChatEvent) =>
         usage,
         finishReason,
         lifecycle,
+        reasoningField,
       },
       events,
     ] as const
@@ -482,7 +510,12 @@ export const protocol = Protocol.make({
   },
   stream: {
     event: Protocol.jsonEvent(OpenAIChatEvent),
-    initial: () => ({ tools: ToolStream.empty<number>(), toolCallEvents: [], lifecycle: Lifecycle.initial() }),
+    initial: () => ({
+      tools: ToolStream.empty<number>(),
+      toolCallEvents: [],
+      lifecycle: Lifecycle.initial(),
+      reasoningField: undefined,
+    }),
     step,
     onHalt: finishEvents,
   },

packages/ai/src/protocols/openai-responses.ts

@@ -835,7 +835,9 @@ const onOutputItemDone = Effect.fn("OpenAIResponses.onOutputItemDone")(function*
       {
         ...state,
         lifecycle,
-        hasFunctionCall: resultEvents.some(LLMEvent.is.toolCall) ? true : state.hasFunctionCall,
+        hasFunctionCall:
+          resultEvents.some((event) => LLMEvent.is.toolCall(event) || LLMEvent.is.toolInputError(event)) ||
+          state.hasFunctionCall,
         tools: result.tools,
       },
       events,

packages/ai/src/protocols/utils/tool-stream.ts

@@ -1,5 +1,5 @@
 import { Effect } from "effect"
-import { LLMError, LLMEvent, type ProviderMetadata, type ToolCall } from "../../schema"
+import { LLMError, LLMEvent, type ProviderMetadata, type ToolCall, type ToolInputError } from "../../schema"
 import { eventError, parseToolInput, type ToolAccumulator } from "../shared"
 
 type StreamKey = string | number
@@ -53,6 +53,7 @@ const inputStart = (tool: PendingTool) =>
   LLMEvent.toolInputStart({
     id: tool.id,
     name: tool.name,
+    providerExecuted: tool.providerExecuted ? true : undefined,
     providerMetadata: tool.providerMetadata,
   })
 
@@ -63,19 +64,38 @@ const inputDelta = (tool: PendingTool, text: string) =>
     text,
   })
 
-const toolCall = (route: string, tool: PendingTool, inputOverride?: string) =>
-  parseToolInput(route, tool.name, inputOverride ?? tool.input).pipe(
-    Effect.map(
-      (input): ToolCall =>
-        LLMEvent.toolCall({
-          id: tool.id,
-          name: tool.name,
-          input,
-          providerExecuted: tool.providerExecuted ? true : undefined,
-          providerMetadata: tool.providerMetadata,
-        }),
+const toolCall = (route: string, tool: PendingTool, inputOverride?: string) => {
+  const raw = inputOverride ?? tool.input
+  return parseToolInput(route, tool.name, raw).pipe(
+    Effect.map((input): ToolCall | ToolInputError =>
+      LLMEvent.toolCall({
+        id: tool.id,
+        name: tool.name,
+        input,
+        providerExecuted: tool.providerExecuted ? true : undefined,
+        providerMetadata: tool.providerMetadata,
+      }),
+    ),
+    Effect.catch((error) =>
+      tool.providerExecuted
+        ? Effect.fail(error)
+        : Effect.succeed(
+            LLMEvent.toolInputError({
+              id: tool.id,
+              name: tool.name,
+              raw,
+              message: error.reason.message,
+              providerMetadata: tool.providerMetadata,
+            }),
+          ),
     ),
   )
+}
+
+const finishEvents = (tool: PendingTool, event: ToolCall | ToolInputError): ReadonlyArray<LLMEvent> =>
+  event.type === "tool-input-error"
+    ? [event]
+    : [LLMEvent.toolInputEnd({ id: tool.id, name: tool.name, providerMetadata: tool.providerMetadata }), event]
 
 /** Store the updated tool and produce the optional public delta event. */
 const appendTool = <K extends StreamKey>(
@@ -158,8 +178,9 @@ export const appendExisting = <K extends StreamKey>(
 
 /**
  * Finalize one pending tool call: parse the accumulated raw JSON, remove it
- * from state, and return the optional public `tool-call` event. Missing keys are
- * a no-op because some providers emit stop events for non-tool content blocks.
+ * from state, and return either a call or a non-executable local input error.
+ * Missing keys are a no-op because some providers emit stop events for
+ * non-tool content blocks.
  */
 export const finish = <K extends StreamKey>(route: string, tools: State<K>, key: K) =>
   Effect.gen(function* () {
@@ -167,10 +188,7 @@ export const finish = <K extends StreamKey>(route: string, tools: State<K>, key:
     if (!tool) return { tools }
     return {
       tools: withoutTool(tools, key),
-      events: [
-        LLMEvent.toolInputEnd({ id: tool.id, name: tool.name, providerMetadata: tool.providerMetadata }),
-        yield* toolCall(route, tool),
-      ],
+      events: finishEvents(tool, yield* toolCall(route, tool)),
     }
   })
 
@@ -185,17 +203,14 @@ export const finishWithInput = <K extends StreamKey>(route: string, tools: State
     if (!tool) return { tools }
     return {
       tools: withoutTool(tools, key),
-      events: [
-        LLMEvent.toolInputEnd({ id: tool.id, name: tool.name, providerMetadata: tool.providerMetadata }),
-        yield* toolCall(route, tool, input),
-      ],
+      events: finishEvents(tool, yield* toolCall(route, tool, input)),
     }
   })
 
 /**
  * Finalize every pending tool call at once. OpenAI Chat has this shape: it does
- * not emit per-tool stop events, so all accumulated calls finish when the choice
- * receives a terminal `finish_reason`.
+ * not emit per-tool stop events, so all accumulated calls finish independently
+ * when the choice receives a terminal `finish_reason`.
  */
 export const finishAll = <K extends StreamKey>(route: string, tools: State<K>) =>
   Effect.gen(function* () {
@@ -205,12 +220,7 @@ export const finishAll = <K extends StreamKey>(route: string, tools: State<K>) =
     return {
       tools: empty<K>(),
       events: yield* Effect.forEach(pending, (tool) =>
-        toolCall(route, tool).pipe(
-          Effect.map((call) => [
-            LLMEvent.toolInputEnd({ id: tool.id, name: tool.name, providerMetadata: tool.providerMetadata }),
-            call,
-          ]),
-        ),
+        toolCall(route, tool).pipe(Effect.map((event) => finishEvents(tool, event))),
       ).pipe(Effect.map((events) => events.flat())),
     }
   })

packages/ai/src/schema/events.ts

@@ -129,6 +129,7 @@ export const ToolInputStart = Schema.Struct({
   type: Schema.tag("tool-input-start"),
   id: ToolCallID,
   name: Schema.String,
+  providerExecuted: Schema.optional(Schema.Boolean),
   providerMetadata: Schema.optional(ProviderMetadata),
 }).annotate({ identifier: "LLM.Event.ToolInputStart" })
 export type ToolInputStart = Schema.Schema.Type<typeof ToolInputStart>
@@ -149,6 +150,17 @@ export const ToolInputEnd = Schema.Struct({
 }).annotate({ identifier: "LLM.Event.ToolInputEnd" })
 export type ToolInputEnd = Schema.Schema.Type<typeof ToolInputEnd>
 
+/** A local tool call that could not be decoded. `raw` is diagnostic-only. */
+export const ToolInputError = Schema.Struct({
+  type: Schema.tag("tool-input-error"),
+  id: ToolCallID,
+  name: Schema.String,
+  raw: Schema.String,
+  message: Schema.String,
+  providerMetadata: Schema.optional(ProviderMetadata),
+}).annotate({ identifier: "LLM.Event.ToolInputError" })
+export type ToolInputError = Schema.Schema.Type<typeof ToolInputError>
+
 export const ToolCall = Schema.Struct({
   type: Schema.tag("tool-call"),
   id: ToolCallID,
@@ -216,6 +228,7 @@ const llmEventTagged = Schema.Union([
   ToolInputStart,
   ToolInputDelta,
   ToolInputEnd,
+  ToolInputError,
   ToolCall,
   ToolResult,
   ToolError,
@@ -253,6 +266,8 @@ export const LLMEvent = Object.assign(llmEventTagged, {
   toolInputDelta: (input: WithID<ToolInputDelta, ToolCallID>) =>
     ToolInputDelta.make({ ...input, id: toolCallID(input.id) }),
   toolInputEnd: (input: WithID<ToolInputEnd, ToolCallID>) => ToolInputEnd.make({ ...input, id: toolCallID(input.id) }),
+  toolInputError: (input: WithID<ToolInputError, ToolCallID>) =>
+    ToolInputError.make({ ...input, id: toolCallID(input.id) }),
   toolCall: (input: WithID<ToolCall, ToolCallID>) => ToolCall.make({ ...input, id: toolCallID(input.id) }),
   toolResult: (input: WithID<ToolResult, ToolCallID>) =>
     ToolResult.make({
@@ -283,6 +298,7 @@ export const LLMEvent = Object.assign(llmEventTagged, {
     toolInputStart: llmEventTagged.guards["tool-input-start"],
     toolInputDelta: llmEventTagged.guards["tool-input-delta"],
     toolInputEnd: llmEventTagged.guards["tool-input-end"],
+    toolInputError: llmEventTagged.guards["tool-input-error"],
     toolCall: llmEventTagged.guards["tool-call"],
     toolResult: llmEventTagged.guards["tool-result"],
     toolError: llmEventTagged.guards["tool-error"],
@@ -548,6 +564,10 @@ const reduceResponseState = (state: ResponseState, event: LLMEvent): ResponseSta
       return reduceToolInputDelta(next, event)
     case "tool-input-end":
       return reduceToolInputEnd(next, event)
+    case "tool-input-error": {
+      const { [event.id]: _finished, ...toolInputs } = next.toolInputs
+      return { ...next, toolInputs }
+    }
     case "tool-call":
       return reduceToolCall(next, event)
     case "tool-result":

packages/ai/test/fixtures/recordings/anthropic-compatible-messages/minimax-m3-anthropic-compatible-text.json

@@ -0,0 +1,40 @@
+{
+  "version": 1,
+  "metadata": {
+    "provider": "minimax",
+    "protocol": "anthropic-messages",
+    "route": "anthropic-messages",
+    "transport": "http",
+    "model": "MiniMax-M3",
+    "tags": [
+      "prefix:anthropic-compatible-messages",
+      "provider:minimax",
+      "protocol:anthropic-messages",
+      "text",
+      "golden"
+    ],
+    "name": "anthropic-compatible-messages/minimax-m3-anthropic-compatible-text",
+    "recordedAt": "2026-07-18T03:42:22.893Z"
+  },
+  "interactions": [
+    {
+      "transport": "http",
+      "request": {
+        "method": "POST",
+        "url": "https://api.minimax.io/anthropic/v1/messages",
+        "headers": {
+          "anthropic-version": "2023-06-01",
+          "content-type": "application/json"
+        },
+        "body": "{\"model\":\"MiniMax-M3\",\"system\":[{\"type\":\"text\",\"text\":\"You are concise.\"}],\"messages\":[{\"role\":\"user\",\"content\":[{\"type\":\"text\",\"text\":\"Reply exactly with: Hello!\"}]}],\"stream\":true,\"max_tokens\":40,\"temperature\":0}"
+      },
+      "response": {
+        "status": 200,
+        "headers": {
+          "content-type": "text/event-stream; charset=utf-8"
+        },
+        "body": "event: message_start\ndata: {\"type\":\"message_start\",\"message\":{\"id\":\"1a0b363d0882af316faebcec4d4855a8\",\"type\":\"message\",\"role\":\"assistant\",\"content\":[],\"model\":\"MiniMax-M3\",\"stop_reason\":null,\"stop_sequence\":null,\"usage\":{\"input_tokens\":53,\"output_tokens\":0,\"cache_creation_input_tokens\":0,\"cache_read_input_tokens\":114,\"service_tier\":\"standard\"},\"service_tier\":\"standard\"}}\n\nevent: ping\ndata: {\"type\":\"ping\"}\n\nevent: content_block_start\ndata: {\"type\":\"content_block_start\",\"index\":0,\"content_block\":{\"type\":\"text\",\"text\":\"\"}}\n\nevent: content_block_delta\ndata: {\"type\":\"content_block_delta\",\"index\":0,\"delta\":{\"type\":\"text_delta\",\"text\":\"Hello\"}}\n\nevent: content_block_delta\ndata: {\"type\":\"content_block_delta\",\"index\":0,\"delta\":{\"type\":\"text_delta\",\"text\":\"!\"}}\n\nevent: content_block_stop\ndata: {\"type\":\"content_block_stop\",\"index\":0}\n\nevent: message_delta\ndata: {\"type\":\"message_delta\",\"delta\":{\"stop_reason\":\"end_turn\"},\"usage\":{\"input_tokens\":53,\"output_tokens\":2,\"cache_read_input_tokens\":114,\"service_tier\":\"standard\"}}\n\nevent: message_stop\ndata: {\"type\":\"message_stop\"}\n\n"
+      }
+    }
+  ]
+}

packages/ai/test/fixtures/recordings/anthropic-compatible-messages/minimax-m3-anthropic-compatible-tool-call.json

@@ -0,0 +1,41 @@
+{
+  "version": 1,
+  "metadata": {
+    "provider": "minimax",
+    "protocol": "anthropic-messages",
+    "route": "anthropic-messages",
+    "transport": "http",
+    "model": "MiniMax-M3",
+    "tags": [
+      "prefix:anthropic-compatible-messages",
+      "provider:minimax",
+      "protocol:anthropic-messages",
+      "tool",
+      "tool-call",
+      "golden"
+    ],
+    "name": "anthropic-compatible-messages/minimax-m3-anthropic-compatible-tool-call",
+    "recordedAt": "2026-07-18T03:42:23.876Z"
+  },
+  "interactions": [
+    {
+      "transport": "http",
+      "request": {
+        "method": "POST",
+        "url": "https://api.minimax.io/anthropic/v1/messages",
+        "headers": {
+          "anthropic-version": "2023-06-01",
+          "content-type": "application/json"
+        },
+        "body": "{\"model\":\"MiniMax-M3\",\"system\":[{\"type\":\"text\",\"text\":\"Call tools exactly as requested.\"}],\"messages\":[{\"role\":\"user\",\"content\":[{\"type\":\"text\",\"text\":\"Call get_weather with city exactly Paris.\"}]}],\"tools\":[{\"name\":\"get_weather\",\"description\":\"Get current weather for a city.\",\"input_schema\":{\"type\":\"object\",\"properties\":{\"city\":{\"type\":\"string\"}},\"required\":[\"city\"],\"additionalProperties\":false}}],\"tool_choice\":{\"type\":\"tool\",\"name\":\"get_weather\"},\"stream\":true,\"max_tokens\":80,\"temperature\":0}"
+      },
+      "response": {
+        "status": 200,
+        "headers": {
+          "content-type": "text/event-stream; charset=utf-8"
+        },
+        "body": "event: message_start\ndata: {\"type\":\"message_start\",\"message\":{\"id\":\"6731ecc323233459d1792df9a733dd98\",\"type\":\"message\",\"role\":\"assistant\",\"content\":[],\"model\":\"MiniMax-M3\",\"stop_reason\":null,\"stop_sequence\":null,\"usage\":{\"input_tokens\":0,\"output_tokens\":0,\"cache_creation_input_tokens\":0,\"cache_read_input_tokens\":404,\"service_tier\":\"standard\"},\"service_tier\":\"standard\"}}\n\nevent: ping\ndata: {\"type\":\"ping\"}\n\nevent: content_block_start\ndata: {\"type\":\"content_block_start\",\"index\":0,\"content_block\":{\"type\":\"tool_use\",\"id\":\"call_function_vkxtif4epmvm_1\",\"name\":\"get_weather\",\"input\":{}}}\n\nevent: content_block_delta\ndata: {\"type\":\"content_block_delta\",\"index\":0,\"delta\":{\"type\":\"input_json_delta\",\"partial_json\":\"{\\\"city\\\": \\\"Paris\"}}\n\nevent: content_block_delta\ndata: {\"type\":\"content_block_delta\",\"index\":0,\"delta\":{\"type\":\"input_json_delta\",\"partial_json\":\"\\\"}\"}}\n\nevent: content_block_stop\ndata: {\"type\":\"content_block_stop\",\"index\":0}\n\nevent: message_delta\ndata: {\"type\":\"message_delta\",\"delta\":{\"stop_reason\":\"tool_use\"},\"usage\":{\"input_tokens\":290,\"output_tokens\":27,\"cache_read_input_tokens\":114,\"service_tier\":\"standard\"}}\n\nevent: message_stop\ndata: {\"type\":\"message_stop\"}\n\n"
+      }
+    }
+  ]
+}

packages/ai/test/fixtures/recordings/anthropic-compatible-messages/minimax-m3-anthropic-compatible-tool-loop.json

@@ -0,0 +1,60 @@
+{
+  "version": 1,
+  "metadata": {
+    "provider": "minimax",
+    "protocol": "anthropic-messages",
+    "route": "anthropic-messages",
+    "transport": "http",
+    "model": "MiniMax-M3",
+    "tags": [
+      "prefix:anthropic-compatible-messages",
+      "provider:minimax",
+      "protocol:anthropic-messages",
+      "tool",
+      "tool-loop",
+      "golden"
+    ],
+    "name": "anthropic-compatible-messages/minimax-m3-anthropic-compatible-tool-loop",
+    "recordedAt": "2026-07-18T03:42:25.248Z"
+  },
+  "interactions": [
+    {
+      "transport": "http",
+      "request": {
+        "method": "POST",
+        "url": "https://api.minimax.io/anthropic/v1/messages",
+        "headers": {
+          "anthropic-version": "2023-06-01",
+          "content-type": "application/json"
+        },
+        "body": "{\"model\":\"MiniMax-M3\",\"system\":[{\"type\":\"text\",\"text\":\"Use the get_weather tool exactly once. After the tool result, reply exactly: Paris is sunny.\"}],\"messages\":[{\"role\":\"user\",\"content\":[{\"type\":\"text\",\"text\":\"What is the weather in Paris?\"}]}],\"tools\":[{\"name\":\"get_weather\",\"description\":\"Get current weather for a city.\",\"input_schema\":{\"type\":\"object\",\"properties\":{\"city\":{\"type\":\"string\"}},\"required\":[\"city\"],\"additionalProperties\":false}}],\"stream\":true,\"max_tokens\":80,\"temperature\":0}"
+      },
+      "response": {
+        "status": 200,
+        "headers": {
+          "content-type": "text/event-stream; charset=utf-8"
+        },
+        "body": "event: message_start\ndata: {\"type\":\"message_start\",\"message\":{\"id\":\"3807fa12f9ecb9357df511e099da6da0\",\"type\":\"message\",\"role\":\"assistant\",\"content\":[],\"model\":\"MiniMax-M3\",\"stop_reason\":null,\"stop_sequence\":null,\"usage\":{\"input_tokens\":0,\"output_tokens\":0,\"cache_creation_input_tokens\":0,\"cache_read_input_tokens\":417,\"service_tier\":\"standard\"},\"service_tier\":\"standard\"}}\n\nevent: ping\ndata: {\"type\":\"ping\"}\n\nevent: content_block_start\ndata: {\"type\":\"content_block_start\",\"index\":0,\"content_block\":{\"type\":\"tool_use\",\"id\":\"call_function_yr64rwmre4gr_1\",\"name\":\"get_weather\",\"input\":{}}}\n\nevent: content_block_delta\ndata: {\"type\":\"content_block_delta\",\"index\":0,\"delta\":{\"type\":\"input_json_delta\",\"partial_json\":\"{\\\"city\\\": \\\"Paris\"}}\n\nevent: content_block_delta\ndata: {\"type\":\"content_block_delta\",\"index\":0,\"delta\":{\"type\":\"input_json_delta\",\"partial_json\":\"\\\"}\"}}\n\nevent: content_block_stop\ndata: {\"type\":\"content_block_stop\",\"index\":0}\n\nevent: message_delta\ndata: {\"type\":\"message_delta\",\"delta\":{\"stop_reason\":\"tool_use\"},\"usage\":{\"input_tokens\":303,\"output_tokens\":27,\"cache_read_input_tokens\":114,\"service_tier\":\"standard\"}}\n\nevent: message_stop\ndata: {\"type\":\"message_stop\"}\n\n"
+      }
+    },
+    {
+      "transport": "http",
+      "request": {
+        "method": "POST",
+        "url": "https://api.minimax.io/anthropic/v1/messages",
+        "headers": {
+          "anthropic-version": "2023-06-01",
+          "content-type": "application/json"
+        },
+        "body": "{\"model\":\"MiniMax-M3\",\"system\":[{\"type\":\"text\",\"text\":\"Use the get_weather tool exactly once. After the tool result, reply exactly: Paris is sunny.\"}],\"messages\":[{\"role\":\"user\",\"content\":[{\"type\":\"text\",\"text\":\"What is the weather in Paris?\"}]},{\"role\":\"assistant\",\"content\":[{\"type\":\"tool_use\",\"id\":\"call_function_yr64rwmre4gr_1\",\"name\":\"get_weather\",\"input\":{\"city\":\"Paris\"}}]},{\"role\":\"user\",\"content\":[{\"type\":\"tool_result\",\"tool_use_id\":\"call_function_yr64rwmre4gr_1\",\"content\":\"{\\\"temperature\\\":22,\\\"condition\\\":\\\"sunny\\\"}\"}]}],\"tools\":[{\"name\":\"get_weather\",\"description\":\"Get current weather for a city.\",\"input_schema\":{\"type\":\"object\",\"properties\":{\"city\":{\"type\":\"string\"}},\"required\":[\"city\"],\"additionalProperties\":false}}],\"stream\":true,\"max_tokens\":80,\"temperature\":0}"
+      },
+      "response": {
+        "status": 200,
+        "headers": {
+          "content-type": "text/event-stream; charset=utf-8"
+        },
+        "body": "event: message_start\ndata: {\"type\":\"message_start\",\"message\":{\"id\":\"92f8a1e86f29946eb2699d40a088fc08\",\"type\":\"message\",\"role\":\"assistant\",\"content\":[],\"model\":\"MiniMax-M3\",\"stop_reason\":null,\"stop_sequence\":null,\"usage\":{\"input_tokens\":41,\"output_tokens\":0,\"cache_creation_input_tokens\":0,\"cache_read_input_tokens\":430,\"service_tier\":\"standard\"},\"service_tier\":\"standard\"}}\n\nevent: ping\ndata: {\"type\":\"ping\"}\n\nevent: content_block_start\ndata: {\"type\":\"content_block_start\",\"index\":0,\"content_block\":{\"type\":\"text\",\"text\":\"\"}}\n\nevent: content_block_delta\ndata: {\"type\":\"content_block_delta\",\"index\":0,\"delta\":{\"type\":\"text_delta\",\"text\":\"Paris\"}}\n\nevent: content_block_delta\ndata: {\"type\":\"content_block_delta\",\"index\":0,\"delta\":{\"type\":\"text_delta\",\"text\":\" is sunny.\"}}\n\nevent: content_block_stop\ndata: {\"type\":\"content_block_stop\",\"index\":0}\n\nevent: message_delta\ndata: {\"type\":\"message_delta\",\"delta\":{\"stop_reason\":\"end_turn\"},\"usage\":{\"input_tokens\":41,\"output_tokens\":4,\"cache_read_input_tokens\":430,\"service_tier\":\"standard\"}}\n\nevent: message_stop\ndata: {\"type\":\"message_stop\"}\n\n"
+      }
+    }
+  ]
+}

packages/ai/test/fixtures/recordings/openrouter-reasoning.json

@@ -0,0 +1,34 @@
+{
+  "version": 1,
+  "metadata": {
+    "model": "anthropic/claude-sonnet-4.6",
+    "tags": [
+      "prefix:openai-compatible-chat",
+      "provider:openrouter",
+      "protocol:openai-chat",
+      "reasoning"
+    ],
+    "name": "openrouter-reasoning",
+    "recordedAt": "2026-07-18T11:28:39.267Z"
+  },
+  "interactions": [
+    {
+      "transport": "http",
+      "request": {
+        "method": "POST",
+        "url": "https://openrouter.ai/api/v1/chat/completions",
+        "headers": {
+          "content-type": "application/json"
+        },
+        "body": "{\"model\":\"anthropic/claude-sonnet-4.6\",\"messages\":[{\"role\":\"system\",\"content\":\"Think through the arithmetic, then reply with only the final integer.\"},{\"role\":\"user\",\"content\":\"What is 173 multiplied by 219?\"}],\"stream\":true,\"stream_options\":{\"include_usage\":true},\"max_tokens\":1536,\"temperature\":0,\"reasoning\":{\"max_tokens\":1024}}"
+      },
+      "response": {
+        "status": 200,
+        "headers": {
+          "content-type": "text/event-stream"
+        },
+        "body": ": OPENROUTER PROCESSING\n\n: OPENROUTER PROCESSING\n\ndata: {\"id\":\"gen-1784374117-AXXPsQRoclZeQGx2uHeK\",\"object\":\"chat.completion.chunk\",\"created\":1784374117,\"model\":\"anthropic/claude-sonnet-4.6\",\"provider\":\"Anthropic\",\"choices\":[{\"index\":0,\"delta\":{\"content\":\"\",\"role\":\"assistant\",\"reasoning\":\"173\",\"reasoning_details\":[{\"type\":\"reasoning.text\",\"text\":\"173\",\"format\":\"anthropic-claude-v1\",\"index\":0}]},\"finish_reason\":null,\"native_finish_reason\":null}]}\n\n: OPENROUTER PROCESSING\n\ndata: {\"id\":\"gen-1784374117-AXXPsQRoclZeQGx2uHeK\",\"object\":\"chat.completion.chunk\",\"created\":1784374117,\"model\":\"anthropic/claude-sonnet-4.6\",\"provider\":\"Anthropic\",\"choices\":[{\"index\":0,\"delta\":{\"content\":\"\",\"role\":\"assistant\",\"reasoning\":\" × 219\\n\\n173 × 200 = 34,600\\n173 × 19 = 173 × 20 - 173 = 3,460 - 173 = 3,287\",\"reasoning_details\":[{\"type\":\"reasoning.text\",\"text\":\" × 219\\n\\n173 × 200 = 34,600\\n173 × 19 = 173 × 20 - 173 = 3,460 - 173 = 3,287\",\"format\":\"anthropic-claude-v1\",\"index\":0}]},\"finish_reason\":null,\"native_finish_reason\":null}]}\n\ndata: {\"id\":\"gen-1784374117-AXXPsQRoclZeQGx2uHeK\",\"object\":\"chat.completion.chunk\",\"created\":1784374117,\"model\":\"anthropic/claude-sonnet-4.6\",\"provider\":\"Anthropic\",\"choices\":[{\"index\":0,\"delta\":{\"content\":\"\",\"role\":\"assistant\",\"reasoning\":\"\\n\\n34,600 + 3,287 = 37,887\",\"reasoning_details\":[{\"type\":\"reasoning.text\",\"text\":\"\\n\\n34,600 + 3,287 = 37,887\",\"format\":\"anthropic-claude-v1\",\"index\":0}]},\"finish_reason\":null,\"native_finish_reason\":null}]}\n\ndata: {\"id\":\"gen-1784374117-AXXPsQRoclZeQGx2uHeK\",\"object\":\"chat.completion.chunk\",\"created\":1784374117,\"model\":\"anthropic/claude-sonnet-4.6\",\"provider\":\"Anthropic\",\"choices\":[{\"index\":0,\"delta\":{\"content\":\"\",\"role\":\"assistant\",\"reasoning_details\":[{\"type\":\"reasoning.text\",\"signature\":\"EtgCCosBCA8YAipA0W4viH3kgBs43Cl5ewwVBPXTQElvzfbA2TLF4iSbKy9ZZDCSDjjAlF3Bs4ELEnP3vrrTuTioC6OB380lXQdyIDIRY2xhdWRlLXNvbm5ldC00LTY4AEIIdGhpbmtpbmdaJDRjMGYwNDZmLTI1ZmQtNDVmYi1iZmIzLWEwOGE4ZTI0OWNhNxIMMiUlJC3x/5p5PuTwGgwlc8eipZyoM94BHwMiMO45uQx/ymeOjbugi7RDVPZ4jZXSIiEbVi2CD7zPjAK5fFQoVGP1HD55v9CER823JCp6Dg5Xb7Lrk6NUd1XN2KTKrttK7mATE+IBrDTFmor/1cNeg+9gjIbxM/jn/6L5HPmh3/esEVu24Q0IGLZVoE7cTgGgxsrceKMD71Jp2XQgIWD8ltsPfWw3gSc4p+z18UuPN6LuR0mHHENTnClHrAPnOrxbDIl4ZwZgMX8YAQ==\",\"format\":\"anthropic-claude-v1\",\"index\":0}]},\"finish_reason\":null,\"native_finish_reason\":null}]}\n\ndata: {\"id\":\"gen-1784374117-AXXPsQRoclZeQGx2uHeK\",\"object\":\"chat.completion.chunk\",\"created\":1784374117,\"model\":\"anthropic/claude-sonnet-4.6\",\"provider\":\"Anthropic\",\"choices\":[{\"index\":0,\"delta\":{\"content\":\"37887\",\"role\":\"assistant\"},\"finish_reason\":null,\"native_finish_reason\":null}]}\n\ndata: {\"id\":\"gen-1784374117-AXXPsQRoclZeQGx2uHeK\",\"object\":\"chat.completion.chunk\",\"created\":1784374117,\"model\":\"anthropic/claude-sonnet-4.6\",\"provider\":\"Anthropic\",\"choices\":[{\"index\":0,\"delta\":{\"content\":\"\",\"role\":\"assistant\",\"reasoning\":null},\"finish_reason\":\"stop\",\"native_finish_reason\":\"end_turn\"}]}\n\ndata: {\"id\":\"gen-1784374117-AXXPsQRoclZeQGx2uHeK\",\"object\":\"chat.completion.chunk\",\"created\":1784374117,\"model\":\"anthropic/claude-sonnet-4.6\",\"provider\":\"Anthropic\",\"service_tier\":\"default\",\"choices\":[{\"index\":0,\"delta\":{\"content\":\"\",\"role\":\"assistant\"},\"finish_reason\":\"stop\",\"native_finish_reason\":\"end_turn\"}],\"usage\":{\"prompt_tokens\":61,\"completion_tokens\":80,\"total_tokens\":141,\"cost\":0.001383,\"is_byok\":false,\"prompt_tokens_details\":{\"cached_tokens\":0,\"cache_write_tokens\":0,\"audio_tokens\":0,\"video_tokens\":0},\"cache_creation\":{\"ephemeral_5m_input_tokens\":0,\"ephemeral_1h_input_tokens\":0},\"cost_details\":{\"upstream_inference_cost\":0.001383,\"upstream_inference_prompt_cost\":0.000183,\"upstream_inference_completions_cost\":0.0012},\"completion_tokens_details\":{\"reasoning_tokens\":29,\"image_tokens\":0,\"audio_tokens\":0}}}\n\ndata: [DONE]\n\n"
+      }
+    }
+  ]
+}

packages/ai/test/provider/anthropic-messages.test.ts

@@ -484,6 +484,30 @@ describe("Anthropic Messages route", () => {
     }),
   )
 
+  it.effect("keeps malformed server tool input terminal", () =>
+    Effect.gen(function* () {
+      const body = sseEvents(
+        { type: "message_start", message: { usage: { input_tokens: 5 } } },
+        {
+          type: "content_block_start",
+          index: 0,
+          content_block: { type: "server_tool_use", id: "call_1", name: "web_search" },
+        },
+        {
+          type: "content_block_delta",
+          index: 0,
+          delta: { type: "input_json_delta", partial_json: '{"query":"partial' },
+        },
+        { type: "content_block_stop", index: 0 },
+      )
+
+      const error = yield* LLMClient.generate(request).pipe(Effect.provide(fixedResponse(body)), Effect.flip)
+
+      expect(error).toBeInstanceOf(LLMError)
+      expect(error.message).toContain("Invalid JSON input for anthropic-messages tool call web_search")
+    }),
+  )
+
   it.effect("fails with a typed provider error for stream error frames", () =>
     Effect.gen(function* () {
       const error = yield* LLMClient.generate(request).pipe(

packages/ai/test/provider/bedrock-converse.test.ts

@@ -303,6 +303,32 @@ describe("Bedrock Converse route", () => {
     }),
   )
 
+  it.effect("emits malformed tool input as an unexecuted tool error", () =>
+    Effect.gen(function* () {
+      const body = eventStreamBody(
+        ["messageStart", { role: "assistant" }],
+        [
+          "contentBlockStart",
+          {
+            contentBlockIndex: 0,
+            start: { toolUse: { toolUseId: "tool_1", name: "lookup" } },
+          },
+        ],
+        ["contentBlockDelta", { contentBlockIndex: 0, delta: { toolUse: { input: '{"query":"partial' } } }],
+        ["contentBlockStop", { contentBlockIndex: 0 }],
+        ["messageStop", { stopReason: "end_turn" }],
+      )
+      const response = yield* LLMClient.generate(baseRequest).pipe(Effect.provide(fixedBytes(body)))
+
+      expect(response.events.find((event) => event.type === "tool-input-error")).toMatchObject({
+        id: "tool_1",
+        name: "lookup",
+        raw: '{"query":"partial',
+      })
+      expect(response.finishReason).toBe("tool-calls")
+    }),
+  )
+
   it.effect("decodes reasoning deltas", () =>
     Effect.gen(function* () {
       const body = eventStreamBody(

packages/ai/test/provider/golden.recorded.test.ts

@@ -1,4 +1,5 @@
 import * as Anthropic from "../../src/providers/anthropic"
+import * as AnthropicCompatible from "../../src/providers/anthropic-compatible"
 import { CloudflareAIGateway, CloudflareWorkersAI } from "../../src/providers/cloudflare"
 import * as Google from "../../src/providers/google"
 import * as OpenAI from "../../src/providers/openai"
@@ -17,6 +18,11 @@ const anthropic = Anthropic.configure({
 })
 const anthropicHaiku = anthropic.model("claude-haiku-4-5-20251001")
 const anthropicOpus = anthropic.model("claude-opus-4-7")
+const minimax = AnthropicCompatible.configure({
+  apiKey: process.env.MINIMAX_API_KEY ?? "fixture",
+  baseURL: "https://api.minimax.io/anthropic/v1",
+  provider: "minimax",
+}).model("MiniMax-M3")
 const google = Google.configure({ apiKey: process.env.GOOGLE_GENERATIVE_AI_API_KEY ?? "fixture" })
 const gemini = google.model("gemini-2.5-flash")
 const xai = XAI.configure({ apiKey: process.env.XAI_API_KEY ?? "fixture" })
@@ -108,6 +114,15 @@ describeRecordedGoldenScenarios([
       { id: "image-tool-result", temperature: false, maxTokens: 40 },
     ],
   },
+  {
+    name: "MiniMax M3 Anthropic-compatible",
+    prefix: "anthropic-compatible-messages",
+    protocol: "anthropic-messages",
+    model: minimax,
+    requires: ["MINIMAX_API_KEY"],
+    options: { redact: { allowRequestHeaders: ["anthropic-version"] } },
+    scenarios: ["text", "tool-call", "tool-loop"],
+  },
   {
     name: "Gemini 2.5 Flash",
     prefix: "gemini",

packages/ai/test/provider/openai-chat-reasoning.recorded.test.ts

@@ -0,0 +1,67 @@
+import { describe, expect } from "bun:test"
+import { Effect } from "effect"
+import { LLM, LLMEvent } from "../../src"
+import * as OpenAICompatible from "../../src/providers/openai-compatible"
+import * as OpenRouter from "../../src/providers/openrouter"
+import { LLMClient } from "../../src/route"
+import { recordedTests } from "../recorded-test"
+
+const cases = [
+  {
+    name: "OpenRouter",
+    model: OpenRouter.configure({
+      apiKey: process.env.OPENROUTER_API_KEY ?? "fixture",
+      providerOptions: { openrouter: { reasoning: { max_tokens: 1024 } } },
+    }).model("anthropic/claude-sonnet-4.6"),
+    requires: ["OPENROUTER_API_KEY"],
+    cassette: "openrouter-reasoning",
+  },
+  {
+    name: "Vercel AI Gateway",
+    model: OpenAICompatible.configure({
+      provider: "vercel-ai-gateway",
+      baseURL: "https://ai-gateway.vercel.sh/v1",
+      apiKey: process.env.AI_GATEWAY_API_KEY ?? "fixture",
+      http: { body: { reasoning: { enabled: true, max_tokens: 1024 } } },
+    }).model("anthropic/claude-sonnet-4.6"),
+    requires: ["AI_GATEWAY_API_KEY"],
+    cassette: "vercel-ai-gateway-reasoning",
+  },
+] as const
+
+for (const item of cases) {
+  const recorded = recordedTests({
+    prefix: "openai-compatible-chat",
+    provider: item.model.provider,
+    protocol: "openai-chat",
+    requires: item.requires,
+    tags: ["reasoning"],
+    metadata: { model: item.model.id },
+  })
+
+  describe(`${item.name} reasoning recorded`, () => {
+    recorded.effect.with(
+      "streams scalar reasoning",
+      { cassette: item.cassette },
+      () =>
+        Effect.gen(function* () {
+          const response = yield* LLMClient.generate(
+            LLM.request({
+              model: item.model,
+              system: "Think through the arithmetic, then reply with only the final integer.",
+              prompt: "What is 173 multiplied by 219?",
+              generation: { maxTokens: 1536, temperature: 0 },
+            }),
+          )
+
+          expect(response.text.replaceAll(",", "").trim()).toBe("37887")
+          expect(response.reasoning.length).toBeGreaterThan(0)
+          expect(response.events.some(LLMEvent.is.reasoningDelta)).toBe(true)
+          expect(response.message.content.find((part) => part.type === "reasoning")?.providerMetadata).toEqual({
+            openai: { reasoningField: "reasoning" },
+          })
+        }),
+      30_000,
+    )
+  })
+}

packages/ai/test/provider/openai-chat.test.ts

@@ -540,29 +540,33 @@ describe("OpenAI Chat route", () => {
     }),
   )
 
-  it.effect("parses OpenAI-compatible reasoning content deltas", () =>
+  it.effect("parses and replays OpenAI-compatible reasoning fields", () =>
     Effect.gen(function* () {
-      const body = sseEvents(
-        { choices: [{ delta: { reasoning_content: "thinking" } }] },
-        { choices: [{ delta: { content: "Hello" } }] },
-        { choices: [{ delta: {}, finish_reason: "stop" }] },
-      )
+      const fields = ["reasoning_content", "reasoning", "reasoning_text"] as const
+      for (const field of fields) {
+        const response = yield* LLMClient.generate(request).pipe(
+          Effect.provide(
+            fixedResponse(
+              sseEvents(
+                { choices: [{ delta: { [field]: "thinking" } }] },
+                { choices: [{ delta: { content: "Hello" } }] },
+                { choices: [{ delta: {}, finish_reason: "stop" }] },
+              ),
+            ),
+          ),
+        )
 
-      const response = yield* LLMClient.generate(request).pipe(Effect.provide(fixedResponse(body)))
+        expect(response.reasoning).toBe("thinking")
+        expect(response.text).toBe("Hello")
+        expect(response.message.content.find((part) => part.type === "reasoning")?.providerMetadata).toEqual({
+          openai: { reasoningField: field },
+        })
 
-      expect(response.reasoning).toBe("thinking")
-      expect(response.text).toBe("Hello")
-      expect(response.events).toMatchObject([
-        { type: "step-start", index: 0 },
-        { type: "reasoning-start", id: "reasoning-0" },
-        { type: "reasoning-delta", id: "reasoning-0", text: "thinking" },
-        { type: "reasoning-end", id: "reasoning-0" },
-        { type: "text-start", id: "text-0" },
-        { type: "text-delta", id: "text-0", text: "Hello" },
-        { type: "text-end", id: "text-0" },
-        { type: "step-finish", index: 0, reason: "stop" },
-        { type: "finish", reason: "stop" },
-      ])
+        const replay = yield* LLMClient.prepare<OpenAIChat.OpenAIChatBody>(
+          LLM.request({ model, messages: [response.message] }),
+        )
+        expect(replay.body.messages).toEqual([{ role: "assistant", content: "Hello", [field]: "thinking" }])
+      }
     }),
   )
 

packages/ai/test/provider/openai-responses.test.ts

@@ -1,7 +1,7 @@
 import { describe, expect } from "bun:test"
 import { ConfigProvider, Effect, Layer, Stream } from "effect"
 import { Headers, HttpClientRequest } from "effect/unstable/http"
-import { LLM, LLMError, Message, Model, ToolCallPart, Usage } from "../../src"
+import { LLM, LLMError, LLMEvent, Message, Model, ToolCallPart, Usage } from "../../src"
 import { Auth, LLMClient, RequestExecutor, WebSocketExecutor } from "../../src/route"
 import * as Azure from "../../src/providers/azure"
 import * as OpenAI from "../../src/providers/openai"
@@ -1259,6 +1259,71 @@ describe("OpenAI Responses route", () => {
     }),
   )
 
+  it.effect("emits malformed final function arguments as an unexecuted tool error", () =>
+    Effect.gen(function* () {
+      const body = sseEvents(
+        {
+          type: "response.output_item.added",
+          item: { type: "function_call", id: "item_1", call_id: "call_1", name: "lookup", arguments: "" },
+        },
+        { type: "response.function_call_arguments.delta", item_id: "item_1", delta: '{"query":"streamed"}' },
+        {
+          type: "response.output_item.done",
+          item: {
+            type: "function_call",
+            id: "item_1",
+            call_id: "call_1",
+            name: "lookup",
+            arguments: '{"query":"partial',
+          },
+        },
+        { type: "response.completed", response: { usage: { input_tokens: 5, output_tokens: 1 } } },
+      )
+      const response = yield* LLMClient.generate(
+        LLM.updateRequest(request, {
+          tools: [{ name: "lookup", description: "Lookup data", inputSchema: { type: "object" } }],
+        }),
+      ).pipe(Effect.provide(fixedResponse(body)))
+
+      expect(response.events.find(LLMEvent.is.toolInputError)).toEqual({
+        type: "tool-input-error",
+        id: "call_1",
+        name: "lookup",
+        raw: '{"query":"partial',
+        message: "Invalid JSON input for openai-responses tool call lookup",
+        providerMetadata: { openai: { itemId: "item_1" } },
+      })
+      expect(response.finishReason).toBe("tool-calls")
+      expect(response.events.some(LLMEvent.is.toolCall)).toBeFalse()
+    }),
+  )
+
+  it.effect("settles malformed function arguments when output_item.added is absent", () =>
+    Effect.gen(function* () {
+      const body = sseEvents(
+        {
+          type: "response.output_item.done",
+          item: {
+            type: "function_call",
+            id: "item_1",
+            call_id: "call_1",
+            name: "lookup",
+            arguments: '{"query":"partial',
+          },
+        },
+        { type: "response.completed", response: { usage: { input_tokens: 5, output_tokens: 1 } } },
+      )
+      const response = yield* LLMClient.generate(request).pipe(Effect.provide(fixedResponse(body)))
+
+      expect(response.events.find(LLMEvent.is.toolInputError)).toMatchObject({
+        id: "call_1",
+        name: "lookup",
+        raw: '{"query":"partial',
+      })
+      expect(response.finishReason).toBe("tool-calls")
+    }),
+  )
+
   it.effect("decodes web_search_call as provider-executed tool-call + tool-result", () =>
     Effect.gen(function* () {
       const item = {

packages/ai/test/response.test.ts

@@ -95,4 +95,20 @@ describe("LLMResponse reducer", () => {
       { type: "tool-call", id: "call_1", name: "lookup", input: { query: "weather" } },
     ])
   })
+
+  test("clears malformed tool input without appending an executable call", () => {
+    const state = reduce([
+      LLMEvent.toolInputStart({ id: "call_1", name: "lookup" }),
+      LLMEvent.toolInputDelta({ id: "call_1", name: "lookup", text: '{"query":"partial' }),
+      LLMEvent.toolInputError({
+        id: "call_1",
+        name: "lookup",
+        raw: '{"query":"partial',
+        message: "Invalid JSON input",
+      }),
+    ])
+
+    expect(state.toolInputs).toEqual({})
+    expect(state.message.content).toEqual([])
+  })
 })

packages/ai/test/tool-stream.test.ts

@@ -64,6 +64,75 @@ describe("ToolStream", () => {
     }),
   )
 
+  it.effect("finalizes malformed local input as a non-executable tool error", () =>
+    Effect.gen(function* () {
+      const tools = ToolStream.start(ToolStream.empty<string>(), "item_1", {
+        id: "call_1",
+        name: "lookup",
+        input: '{"query":"partial',
+      })
+      const finished = yield* ToolStream.finish(ADAPTER, tools, "item_1")
+
+      expect(finished).toEqual({
+        tools: {},
+        events: [
+          {
+            type: "tool-input-error",
+            id: "call_1",
+            name: "lookup",
+            raw: '{"query":"partial',
+            message: "Invalid JSON input for test-route tool call lookup",
+          },
+        ],
+      })
+    }),
+  )
+
+  it.effect("preserves valid siblings when one parallel input is malformed", () =>
+    Effect.gen(function* () {
+      const valid = ToolStream.start(ToolStream.empty<number>(), 0, {
+        id: "call_valid",
+        name: "lookup",
+        input: '{"query":"weather"}',
+      })
+      const tools = ToolStream.start(valid, 1, {
+        id: "call_invalid",
+        name: "lookup",
+        input: '{"query":"partial',
+      })
+      const finished = yield* ToolStream.finishAll(ADAPTER, tools)
+
+      expect(finished).toEqual({
+        tools: {},
+        events: [
+          { type: "tool-input-end", id: "call_valid", name: "lookup" },
+          { type: "tool-call", id: "call_valid", name: "lookup", input: { query: "weather" } },
+          {
+            type: "tool-input-error",
+            id: "call_invalid",
+            name: "lookup",
+            raw: '{"query":"partial',
+            message: "Invalid JSON input for test-route tool call lookup",
+          },
+        ],
+      })
+    }),
+  )
+
+  it.effect("keeps malformed provider-executed input terminal", () =>
+    Effect.gen(function* () {
+      const tools = ToolStream.start(ToolStream.empty<string>(), "item_1", {
+        id: "call_1",
+        name: "web_search",
+        input: '{"query":"partial',
+        providerExecuted: true,
+      })
+      const result = yield* Effect.exit(ToolStream.finish(ADAPTER, tools, "item_1"))
+
+      expect(result._tag).toBe("Failure")
+    }),
+  )
+
   it.effect("preserves providerExecuted and clears all tools", () =>
     Effect.gen(function* () {
       const first: ToolStream.State<number> = ToolStream.start(ToolStream.empty<number>(), 0, {

packages/cli/src/server-process.ts

@@ -54,7 +54,7 @@ const processEffect = Effect.fnUntraced(function* (options: Options) {
       }
       const password =
         options.mode === "service"
-          ? yield* ServiceConfig.password()
+          ? config.password || randomBytes(32).toString("base64url")
           : environmentPassword
             ? Redacted.value(environmentPassword)
             : randomBytes(32).toString("base64url")
@@ -69,7 +69,11 @@ const processEffect = Effect.fnUntraced(function* (options: Options) {
           serviceOptions === undefined
             ? undefined
             : {
-                onListen: (address, shutdown) => register(address, password, instanceID, serviceOptions.file, shutdown),
+                onListen: (address, shutdown) =>
+                  Effect.gen(function* () {
+                    if (!config.password) yield* ServiceConfig.password(password)
+                    return yield* register(address, password, instanceID, serviceOptions.file, shutdown)
+                  }),
               },
       }).pipe(
         Effect.provide(Logger.layer([], { mergeWithExisting: false })),
@@ -154,8 +158,8 @@ const register = Effect.fnUntraced(function* (
 const recognizeIncumbent = Effect.fnUntraced(function* (options: DiscoverOptions, hostname: string, port: number) {
   const found = yield* Service.incumbent({ ...options, url: serviceURL(hostname, port) }).pipe(
     Effect.filterOrFail((value) => value !== undefined),
-    Effect.retry(Schedule.max([Schedule.spaced("100 millis"), Schedule.recurs(60)])),
-    Effect.option,
+    Effect.retry(Schedule.spaced("100 millis")),
+    Effect.timeoutOption("15 seconds"),
   )
   return Option.isSome(found)
 })

packages/cli/test/service.test.ts

@@ -4,6 +4,7 @@ import { Database } from "@opencode-ai/core/database/database"
 import { EventV2 } from "@opencode-ai/core/event"
 import { EventTable } from "@opencode-ai/core/event/sql"
 import { Global } from "@opencode-ai/core/global"
+import { InstallationVersion } from "@opencode-ai/core/installation/version"
 import { Project } from "@opencode-ai/core/project"
 import { ProjectTable } from "@opencode-ai/core/project/sql"
 import { AbsolutePath } from "@opencode-ai/core/schema"
@@ -212,9 +213,10 @@ test("concurrent service processes elect one server", async () => {
   const command = [process.execPath, path.join(import.meta.dir, "../src/index.ts"), "serve", "--service"]
   const registration = path.join(root, "state", "opencode", "service-local.json")
   const port = await availablePort()
+  const config = path.join(root, "config", "opencode", "service-local.json")
   await fs.mkdir(path.join(root, "config", "opencode"), { recursive: true })
-  await fs.writeFile(path.join(root, "config", "opencode", "service-local.json"), JSON.stringify({ port }))
-  const processes = Array.from({ length: 10 }, () => Bun.spawn(command, { env, stderr: "pipe", stdout: "ignore" }))
+  await fs.writeFile(config, JSON.stringify({ port }))
+  const processes = Array.from({ length: 10 }, () => Bun.spawn(command, { env, stderr: "pipe", stdout: "pipe" }))
 
   try {
     const info = await waitForInfo(registration)
@@ -225,8 +227,18 @@ test("concurrent service processes elect one server", async () => {
     )
 
     expect(exited).toEqual(losers.map(() => true))
+    const errors = await Promise.all(
+      losers.map(
+        async (process) => (await new Response(process.stdout).text()) + (await new Response(process.stderr).text()),
+      ),
+    )
+    expect(
+      losers.map((process) => process.exitCode),
+      errors.filter(Boolean).join("\n"),
+    ).toEqual(losers.map(() => 0))
     expect(winner?.exitCode).toBe(null)
     expect(new URL(info.url).port).toBe(String(port))
+    expect((await Bun.file(config).json()).password).toBe(info.password)
     expect(await Bun.file(registration + ".lock").exists()).toBe(false)
     expect(
       await fetch(new URL("/api/health", info.url), {
@@ -244,6 +256,7 @@ test("concurrent service processes elect one server", async () => {
         Bun.sleep(10_000).then(() => false),
       ])
       expect(contenderExited).toBe(true)
+      expect(contender.exitCode).toBe(0)
       expect((await waitForInfo(registration)).id).toBe(info.id)
     } finally {
       contender.kill("SIGTERM")
@@ -265,14 +278,11 @@ test("concurrent service processes elect one server", async () => {
     expect(await waitForExecutionStart(database, sessionID)).toBe(1)
     await Effect.runPromise(Service.stop({ file: registration }).pipe(Effect.provide(NodeFileSystem.layer)))
     await winner?.exited
+    expect(await Bun.file(registration).exists()).toBe(false)
   } finally {
     processes.forEach((process) => process.kill("SIGTERM"))
     await Promise.all(processes.map((process) => process.exited))
-    try {
-      expect(await Bun.file(registration).exists()).toBe(false)
-    } finally {
-      await fs.rm(root, { recursive: true, force: true })
-    }
+    await fs.rm(root, { recursive: true, force: true })
   }
 }, 120_000)
 
@@ -281,8 +291,9 @@ test("configured managed service port overrides the channel default", async () =
   const port = await availablePort()
   const env = serviceEnv(root)
   const registration = path.join(root, "state", "opencode", "service-local.json")
+  const config = path.join(root, "config", "opencode", "service-local.json")
   await fs.mkdir(path.join(root, "config", "opencode"), { recursive: true })
-  await fs.writeFile(path.join(root, "config", "opencode", "service-local.json"), JSON.stringify({ port }))
+  await fs.writeFile(config, JSON.stringify({ port, password: "" }))
   const owner = Bun.spawn([process.execPath, path.join(import.meta.dir, "../src/index.ts"), "serve", "--service"], {
     env,
     stderr: "pipe",
@@ -291,6 +302,8 @@ test("configured managed service port overrides the channel default", async () =
   try {
     const info = await waitForInfo(registration)
     expect(new URL(info.url).port).toBe(String(port))
+    expect(info.password).not.toBe("")
+    expect((await Bun.file(config).json()).password).toBe(info.password)
     await Effect.runPromise(Service.stop({ file: registration }).pipe(Effect.provide(NodeFileSystem.layer)))
     await owner.exited
   } finally {
@@ -302,7 +315,7 @@ test("configured managed service port overrides the channel default", async () =
 
 test("unrelated managed port occupancy reports an actionable conflict", async () => {
   const root = await fs.mkdtemp(path.join(os.tmpdir(), "opencode-service-conflict-"))
-  const listener = Bun.serve({ port: 0, fetch: () => new Response("unrelated") })
+  const listener = Bun.serve({ hostname: "127.0.0.1", port: 0, fetch: () => new Response("unrelated") })
   const port = listener.port
   const registration = path.join(root, "state", "opencode", "service-local.json")
   await fs.mkdir(path.join(root, "config", "opencode"), { recursive: true })
@@ -326,6 +339,109 @@ test("unrelated managed port occupancy reports an actionable conflict", async ()
   }
 }, 30_000)
 
+test("unresponsive managed port occupancy reports a bounded conflict", async () => {
+  const root = await fs.mkdtemp(path.join(os.tmpdir(), "opencode-service-unresponsive-conflict-"))
+  const recognizing = Promise.withResolvers<void>()
+  const requests = { count: 0 }
+  using listener = Bun.serve({
+    hostname: "127.0.0.1",
+    port: 0,
+    fetch() {
+      requests.count += 1
+      if (requests.count === 2) recognizing.resolve()
+      return new Promise<Response>(() => {})
+    },
+  })
+  const registration = path.join(root, "state", "opencode", "service-local.json")
+  await fs.mkdir(path.join(root, "config", "opencode"), { recursive: true })
+  await fs.mkdir(path.dirname(registration), { recursive: true })
+  await fs.writeFile(
+    path.join(root, "config", "opencode", "service-local.json"),
+    JSON.stringify({ port: listener.port }),
+  )
+  const stale = {
+    id: "stale",
+    version: InstallationVersion,
+    url: "http://127.0.0.1:1",
+    pid: process.pid,
+    password: "stale",
+  }
+  await fs.writeFile(registration, JSON.stringify(stale))
+  const contender = Bun.spawn([process.execPath, path.join(import.meta.dir, "../src/index.ts"), "serve", "--service"], {
+    env: serviceEnv(root),
+    stderr: "pipe",
+    stdout: "pipe",
+  })
+
+  try {
+    expect(await Promise.race([recognizing.promise.then(() => true), Bun.sleep(20_000).then(() => false)])).toBe(true)
+    const exitCode = await Promise.race([contender.exited, Bun.sleep(20_000).then(() => undefined)])
+    expect(exitCode).toBe(1)
+    const output = (await new Response(contender.stdout).text()) + (await new Response(contender.stderr).text())
+    expect(output).toContain(`Managed service port ${listener.port} on 127.0.0.1 is already in use by another process`)
+    expect(await Bun.file(registration).json()).toEqual(stale)
+  } finally {
+    contender.kill("SIGTERM")
+    await contender.exited
+    await fs.rm(root, { recursive: true, force: true })
+  }
+}, 45_000)
+
+test("port contender recognizes an incumbent registered during the bind race", async () => {
+  const root = await fs.mkdtemp(path.join(os.tmpdir(), "opencode-service-bind-race-"))
+  const recognizing = Promise.withResolvers<void>()
+  const requests = { count: 0 }
+  using listener = Bun.serve({
+    hostname: "127.0.0.1",
+    port: 0,
+    fetch() {
+      requests.count += 1
+      if (requests.count === 2) recognizing.resolve()
+      return Response.json({ healthy: true, version: InstallationVersion, pid: process.pid }, { status: 503 })
+    },
+  })
+  const registration = path.join(root, "state", "opencode", "service-local.json")
+  const config = path.join(root, "config", "opencode", "service-local.json")
+  await fs.mkdir(path.dirname(config), { recursive: true })
+  await fs.writeFile(config, JSON.stringify({ port: listener.port }))
+  await fs.mkdir(path.dirname(registration), { recursive: true })
+  await fs.writeFile(
+    registration,
+    JSON.stringify({
+      id: "stale",
+      version: InstallationVersion,
+      url: "http://127.0.0.1:1",
+      pid: 2_147_483_647,
+      password: "stale",
+    }),
+  )
+  const contender = Bun.spawn([process.execPath, path.join(import.meta.dir, "../src/index.ts"), "serve", "--service"], {
+    env: serviceEnv(root),
+    stderr: "pipe",
+    stdout: "ignore",
+  })
+
+  try {
+    expect(await Promise.race([recognizing.promise.then(() => true), Bun.sleep(20_000).then(() => false)])).toBe(true)
+    await Bun.sleep(8_000)
+    const info = {
+      id: "incumbent",
+      version: InstallationVersion,
+      url: `http://127.0.0.1:${listener.port}`,
+      pid: process.pid,
+      password: "incumbent",
+    }
+    await fs.writeFile(registration, JSON.stringify(info))
+
+    expect(await Promise.race([contender.exited, Bun.sleep(20_000).then(() => undefined)])).toBe(0)
+    expect(await Bun.file(registration).json()).toEqual(info)
+  } finally {
+    contender.kill("SIGTERM")
+    await contender.exited
+    await fs.rm(root, { recursive: true, force: true })
+  }
+}, 45_000)
+
 test("stale dead registration is replaced after binding the selected port", async () => {
   const root = await fs.mkdtemp(path.join(os.tmpdir(), "opencode-service-stale-"))
   const port = await availablePort()
@@ -375,10 +491,12 @@ test("a failed service stays registered and owns the selected port until stopped
 
   try {
     const info = await waitForInfo(registration)
+    await waitForFailed(info)
     expect(owner.exitCode).toBe(null)
 
     const contender = Bun.spawn(command, { env, stderr: "pipe", stdout: "ignore" })
     expect(await Promise.race([contender.exited.then(() => true), Bun.sleep(10_000).then(() => false)])).toBe(true)
+    expect(contender.exitCode).toBe(0)
     expect((await waitForInfo(registration)).id).toBe(info.id)
     expect(owner.exitCode).toBe(null)
 

packages/client/src/promise/generated/types.ts

@@ -1276,6 +1276,8 @@ export type SessionStepFailed = {
     error: SessionStructuredError
     cost?: MoneyUSD
     tokens?: TokenUsageInfo
+    snapshot?: string
+    files?: Array<string>
   }
 }
 

packages/codemode/interpreter-support.md

@@ -19,7 +19,7 @@ ultimate source of truth.
 - [x] Top-level `await` and `return` through the program's implicit async-function scope.
 - [x] Explicit `return`, final top-level expression as a REPL-style result, and `null` when no value is produced.
 - [x] Program results use JSON-like boundaries, with `undefined` and non-finite numbers normalized to `null`. Tool
-      arguments remain subject to their schema and the outbound-handling gap listed below.
+      arguments follow JSON serialization semantics before their schema applies (see the tools section).
 - [x] Live Date, RegExp, Map, Set, URL, and URLSearchParams values inside CodeMode.
 - [x] Tool calls through the host-provided `tools` tree only.
 - [x] The global `search(...)` built-in: synchronous tool discovery that counts as an admitted tool call and is
@@ -80,7 +80,7 @@ ultimate source of truth.
 - [x] Expression and block function bodies.
 - [x] User callbacks for the supported Array, Map, Set, URLSearchParams, sort, string-replacement, and `Array.from`
       mapper APIs, with one shared acceptance rule everywhere including promise reactions.
-- [x] `Boolean`, `Number`, `String`, `parseInt`, `parseFloat`, and URI helpers as callbacks.
+- [x] `Boolean`, `Number`, `String`, `parseInt`, `parseFloat`, `isFinite`, `isNaN`, and URI helpers as callbacks.
 - [x] Built-in method references as callbacks, such as `values.map(Math.abs)`, `records.map(JSON.stringify)`,
       `items.forEach(console.log)`, and `Promise.resolve(-1).then(Math.abs)`. Extra callback arguments a built-in
       does not consume are ignored, like JS; consumed arguments stay strictly validated (`Math.floor` still rejects a
@@ -157,8 +157,11 @@ ultimate source of truth.
 - [x] Dotted tool names are canonicalized into namespace paths; a path can be both callable and a namespace, and the
       last definition supplied for a canonical path wins.
 - [x] Tool path segments may be named `constructor`, `prototype`, or `__proto__` because paths use inert Map keys.
-- [ ] Reject `undefined` and non-finite numbers in outbound tool arguments before render-only and OpenAPI tools run;
-      retain null normalization for program results and JSON serialization.
+- [x] Outbound tool arguments follow JSON serialization semantics, like `JSON.stringify`: object properties with
+      `undefined` values are dropped, `undefined` array elements and non-finite numbers become `null`, and sparse
+      arrays densify. Tools never receive `undefined` inside their input object, though a bare `tools.t(undefined)`
+      argument still reaches schema decoding as `undefined`. Program results keep the stricter
+      normalization where every `undefined` becomes `null`.
 - [ ] Tokenize and case-fold non-ASCII tool paths, descriptions, and queries for tool search.
 
 ## Objects and properties
@@ -210,9 +213,12 @@ ultimate source of truth.
 - [x] `localeCompare`; locale and options arguments are currently ignored.
 - [x] `toString`, `length`, numeric indexing, spread, and `for...of` by Unicode code point.
 - [x] Static `String.fromCharCode` and `String.fromCodePoint`.
-- [ ] Native argument coercion for supported String methods; for example, `includes(1)` and `slice("1")` currently
-      reject instead of coercing.
-- [ ] Native no-argument parity for `match()` and `search()`.
+- [x] Native argument coercion for supported String methods; for example, `includes(1)` and `slice("1")` coerce like
+      native JS, `split(undefined)` returns the whole string, and `includes`/`startsWith`/`endsWith` reject regular
+      expressions with a native-style `TypeError`. Opaque runtime references still reject as data errors, and
+      `repeat` still requires a finite non-negative count.
+- [x] Native no-argument parity for `match()`, `matchAll()`, and `search()`; all behave as an empty pattern. Present
+      arguments must still be a regular expression or string pattern.
 
 ## Numbers and Math
 
@@ -226,13 +232,16 @@ ultimate source of truth.
 - [x] Math methods: `random`, `max`, `min`, `abs`, `acos`, `acosh`, `asin`, `asinh`, `atan`, `atan2`, `atanh`,
       `floor`, `ceil`, `round`, `trunc`, `sign`, `sqrt`, `cbrt`, `pow`, `hypot`, `cos`, `cosh`, `sin`, `sinh`,
       `tan`, `tanh`, `log`, `log2`, `log10`, `log1p`, `exp`, `expm1`, `f16round`, `fround`, `clz32`, and `imul`.
-- [ ] Native zero-argument behavior for `Number()` and `String()`; they currently do not produce `0` and `""`.
-- [ ] `++` and `--` must use CodeMode numeric coercion and reject opaque runtime references; they currently call host
-      `Number(...)` directly.
-- [ ] Unknown static members must read as `undefined` for feature detection; some currently appear callable or throw
-      during property access.
+- [x] Native zero-argument behavior for `Number()` and `String()`: they produce `0` and `""`, while
+      `Number(undefined)` stays `NaN` and `String(undefined)` stays `"undefined"`.
+- [x] `++` and `--` use CodeMode numeric coercion (numeric strings increment, plain data objects become `NaN`, Dates
+      use their epoch time) and reject opaque runtime references as data errors.
+- [x] Unknown static members on global namespaces and on `Number`/`String`/the coercion functions read as `undefined`
+      for feature detection. Calling any undefined value reports a native-style `TypeError` naming the callee, for
+      example `Math.sumPrecise is not a function.` Blocked members (`constructor`, `__proto__`, ...) still throw,
+      and unknown `Promise` statics keep their descriptive error.
 - [ ] `Math.sumPrecise`.
-- [ ] Global coercing `isFinite` and `isNaN`.
+- [x] Global coercing `isFinite` and `isNaN`; opaque runtime references reject as data errors, like `Number(...)`.
 
 ## JSON and console
 

packages/codemode/src/interpreter/errors.ts

@@ -44,7 +44,7 @@ export const normalizeError = (error: unknown): Diagnostic => {
       message = (value as { message: string }).message
     } else {
       try {
-        message = JSON.stringify(copyOut(value)) ?? String(value)
+        message = JSON.stringify(copyOut(value, "json")) ?? String(value)
       } catch {
         message = String(value)
       }

packages/codemode/src/interpreter/execute.ts

@@ -52,7 +52,7 @@ export const executeWithLimits = <const Provided extends Record<string, unknown>
             logs,
           )
           const value = yield* interpreter.run(program)
-          const result = copyOut(copyIn(value, "Execution result"), true) as DataValue
+          const result = copyOut(copyIn(value, "Execution result"), "nullify") as DataValue
           returned = { value: result, promises }
           const warnings = yield* promises.interrupt()
           return {

packages/codemode/src/interpreter/methods.ts

@@ -12,7 +12,7 @@ import {
   PromiseNamespace,
   UriFunction,
 } from "./model.js"
-import { rejectCircularInsertion, typeofValue } from "./references.js"
+import { containsOpaqueReference, rejectCircularInsertion, typeofValue } from "./references.js"
 import { isBlockedMember, type SafeObject } from "../tool-runtime.js"
 import {
   CodeModeDate,
@@ -137,21 +137,31 @@ export const invokeGlobalMethod = (ref: GlobalMethodReference, args: Array<unkno
   return invokeJsonMethod(ref.name, args, node)
 }
 
+const requireDataArgument = (name: string, index: number, arg: unknown, node: AstNode): unknown => {
+  if (containsOpaqueReference(arg)) {
+    throw new InterpreterRuntimeError(
+      `String.${name} expects argument ${index + 1} to be a data value.`,
+      node,
+      "InvalidDataValue",
+    )
+  }
+  return arg
+}
+
 const invokeStringMethod = (value: string, name: string, args: Array<unknown>, node: AstNode): unknown => {
-  const str = (index: number): string => {
-    const arg = args[index]
-    if (typeof arg !== "string")
-      throw new InterpreterRuntimeError(`String.${name} expects argument ${index + 1} to be a string.`, node)
-    return arg
-  }
-  const num = (index: number): number => {
-    const arg = args[index]
-    if (typeof arg !== "number")
-      throw new InterpreterRuntimeError(`String.${name} expects argument ${index + 1} to be a number.`, node)
-    return arg
-  }
+  // Coerce arguments like native JS; opaque runtime references still reject.
+  const str = (index: number): string => coerceToString(requireDataArgument(name, index, args[index], node))
+  const num = (index: number): number => coerceToNumber(requireDataArgument(name, index, args[index], node))
   const optNum = (index: number): number | undefined => (args[index] === undefined ? undefined : num(index))
   const optStr = (index: number): string | undefined => (args[index] === undefined ? undefined : str(index))
+  const rejectRegex = (): void => {
+    if (args[0] instanceof CodeModeRegExp) {
+      throw new InterpreterRuntimeError(
+        `String.${name} cannot take a regular expression; use regex.test(string) or String.search instead.`,
+        node,
+      ).as("TypeError")
+    }
+  }
 
   let result: unknown
   switch (name) {
@@ -187,8 +197,11 @@ const invokeStringMethod = (value: string, name: string, args: Array<unknown>, n
       break
     }
     case "split": {
-      if (args.length === 0) {
-        result = [value]
+      // Native: an undefined separator returns the whole string, not a split on "undefined",
+      // unless the limit truncates to zero.
+      if (args[0] === undefined) {
+        const requestedLimit = optNum(1)
+        result = requestedLimit !== undefined && requestedLimit >>> 0 === 0 ? [] : [value]
         break
       }
       if (args[0] instanceof CodeModeRegExp) {
@@ -203,12 +216,15 @@ const invokeStringMethod = (value: string, name: string, args: Array<unknown>, n
       result = value.slice(optNum(0), optNum(1))
       break
     case "includes":
+      rejectRegex()
       result = value.includes(str(0), optNum(1))
       break
     case "startsWith":
+      rejectRegex()
       result = value.startsWith(str(0), optNum(1))
       break
     case "endsWith":
+      rejectRegex()
       result = value.endsWith(str(0), optNum(1))
       break
     case "indexOf":
@@ -263,7 +279,7 @@ const invokeStringMethod = (value: string, name: string, args: Array<unknown>, n
     case "repeat": {
       const count = num(0)
       if (!Number.isFinite(count) || count < 0)
-        throw new InterpreterRuntimeError("String.repeat expects a finite non-negative count.", node)
+        throw new InterpreterRuntimeError("String.repeat expects a finite non-negative count.", node).as("RangeError")
       result = value.repeat(count)
       break
     }
@@ -301,6 +317,8 @@ const invokeStringMethod = (value: string, name: string, args: Array<unknown>, n
   return boundedData(result, `String.${name} result`)
 }
 
+export const arrayStatics = new Set(["isArray", "of", "from"])
+
 const invokeArrayStatic = (name: string, args: Array<unknown>, node: AstNode): unknown => {
   switch (name) {
     case "isArray":
@@ -400,11 +418,9 @@ const invokeStringReplacer = <R>(
     if (name === "replace") value.replace(pattern.regex, collect)
     else value.replaceAll(pattern.regex, collect)
   } else {
-    if (typeof pattern !== "string") {
-      throw new InterpreterRuntimeError(`String.${name} expects argument 1 to be a string.`, node)
-    }
-    if (name === "replace") value.replace(pattern, collect)
-    else value.replaceAll(pattern, collect)
+    const search = coerceToString(requireDataArgument(name, 0, pattern, node))
+    if (name === "replace") value.replace(search, collect)
+    else value.replaceAll(search, collect)
   }
 
   return Effect.gen(function* () {

packages/codemode/src/interpreter/model.ts

@@ -105,7 +105,7 @@ export class GlobalMethodReference {
 }
 
 export class CoercionFunction {
-  constructor(readonly name: "Number" | "String" | "Boolean" | "parseInt" | "parseFloat") {}
+  constructor(readonly name: "Number" | "String" | "Boolean" | "parseInt" | "parseFloat" | "isFinite" | "isNaN") {}
 }
 
 export class UriFunction {

packages/codemode/src/interpreter/runtime.ts

@@ -10,6 +10,7 @@ import {
   ErrorConstructorReference,
   GlobalMethodReference,
   GlobalNamespace,
+  type GlobalNamespaceName,
   getArray,
   getBoolean,
   getNode,
@@ -34,7 +35,7 @@ import {
   UriFunction,
 } from "./model.js"
 import { caughtErrorValue, constructErrorValue } from "./errors.js"
-import { type CallbackRunner, invokeArrayFrom, invokeGlobalMethod, invokeIntrinsic } from "./methods.js"
+import { arrayStatics, type CallbackRunner, invokeArrayFrom, invokeGlobalMethod, invokeIntrinsic } from "./methods.js"
 import {
   constructPromise,
   invokePromiseInstanceMethod,
@@ -46,10 +47,11 @@ import { containsOpaqueReference, isRuntimeReference, rejectCircularInsertion, t
 import { ScopeStack } from "./scope.js"
 import { arrayMethods, mapMethods, setMethods, spreadItems } from "../stdlib/collections.js"
 import { consoleMethods, formatConsoleMessage } from "../stdlib/console.js"
-import { dateMethods } from "../stdlib/date.js"
-import { mathConstants } from "../stdlib/math.js"
+import { dateMethods, dateStatics } from "../stdlib/date.js"
+import { jsonStatics } from "../stdlib/json.js"
+import { mathConstants, mathMethods } from "../stdlib/math.js"
 import { numberConstants, numberMethods, numberStatics } from "../stdlib/number.js"
-import { objectMethodsPreservingIdentity } from "../stdlib/object.js"
+import { objectMethodsPreservingIdentity, objectStatics } from "../stdlib/object.js"
 import { promiseStatics } from "../stdlib/promise.js"
 import { escapeRegexHint, regexpMethods, regexpProperties, regexFailureReason } from "../stdlib/regexp.js"
 import { stringMethods, stringStatics } from "../stdlib/string.js"
@@ -57,6 +59,7 @@ import {
   urlMethods,
   urlProperties,
   urlSearchParamsMethods,
+  urlStatics,
   urlWritableProperties,
   invokeUriFunction,
   uriArgument,
@@ -83,6 +86,32 @@ import {
   CodeModeURLSearchParams,
 } from "../values.js"
 
+const globalStaticMembers: Partial<Record<GlobalNamespaceName, Set<string>>> = {
+  Object: objectStatics,
+  Math: mathMethods,
+  JSON: jsonStatics,
+  Array: arrayStatics,
+  console: consoleMethods,
+  Date: dateStatics,
+  URL: urlStatics,
+}
+
+const calleeDescription = (callee: AstNode): string => {
+  if (callee.type === "Identifier") return getString(callee, "name")
+  if (callee.type === "MemberExpression") {
+    const object = getNode(callee, "object")
+    const property = getNode(callee, "property")
+    const key =
+      callee.computed !== true && property.type === "Identifier"
+        ? getString(property, "name")
+        : property.type === "Literal" && typeof property.value === "string"
+          ? property.value
+          : undefined
+    if (object.type === "Identifier" && key !== undefined) return `${getString(object, "name")}.${key}`
+  }
+  return "The called value"
+}
+
 const instanceofValue = (lhs: unknown, rhs: unknown, node: AstNode): boolean => {
   if (rhs instanceof ErrorConstructorReference) {
     const brand = errorBrandName(lhs)
@@ -199,6 +228,8 @@ export class Interpreter<R> {
     globalScope.set("console", { mutable: false, value: new GlobalNamespace("console") })
     globalScope.set("parseInt", { mutable: false, value: new CoercionFunction("parseInt") })
     globalScope.set("parseFloat", { mutable: false, value: new CoercionFunction("parseFloat") })
+    globalScope.set("isFinite", { mutable: false, value: new CoercionFunction("isFinite") })
+    globalScope.set("isNaN", { mutable: false, value: new CoercionFunction("isNaN") })
     globalScope.set("Date", { mutable: false, value: new GlobalNamespace("Date") })
     globalScope.set("RegExp", { mutable: false, value: new GlobalNamespace("RegExp") })
     globalScope.set("Map", { mutable: false, value: new GlobalNamespace("Map") })
@@ -1454,10 +1485,23 @@ export class Interpreter<R> {
       throw new InterpreterRuntimeError(`Unsupported update operator '${operator}'.`, node)
     }
 
+    // CodeMode numeric coercion, not host Number(): null-prototype data objects would make
+    // the host throw during ToPrimitive, and opaque runtime references must reject clearly.
+    const operand = (current: unknown): number => {
+      if (containsOpaqueReference(current)) {
+        throw new InterpreterRuntimeError(
+          `'${operator}' requires a data value in CodeMode.`,
+          argument,
+          "InvalidDataValue",
+        )
+      }
+      return coerceToNumber(current)
+    }
+
     if (argument.type === "Identifier") {
       return Effect.sync(() => {
         const name = getString(argument, "name")
-        const current = Number(this.scopes.get(name, argument))
+        const current = operand(this.scopes.get(name, argument))
         const next = current + increment
         this.scopes.set(name, next, argument)
         return prefix ? next : current
@@ -1466,7 +1510,7 @@ export class Interpreter<R> {
 
     if (argument.type === "MemberExpression") {
       return this.modifyMember(argument, (current) => {
-        const value = Number(current)
+        const value = operand(current)
         const next = value + increment
         return Effect.succeed({ write: true, next, result: prefix ? next : value })
       })
@@ -1563,6 +1607,9 @@ export class Interpreter<R> {
         callable.settle(args[0])
         return undefined
       }
+      if (callable === undefined || callable === null) {
+        throw new InterpreterRuntimeError(`${calleeDescription(callee)} is not a function.`, callee).as("TypeError")
+      }
       throw new InterpreterRuntimeError("Only tools are callable in CodeMode.", callee)
     })
   }
@@ -1833,16 +1880,18 @@ export class Interpreter<R> {
       }
 
       if (objectValue instanceof GlobalNamespace) {
-        if (typeof key !== "string" || isBlockedMember(key)) {
-          throw new InterpreterRuntimeError(
-            `${objectValue.name}.${String(key)} is not available in CodeMode.`,
-            propertyNode,
-          )
+        if (typeof key === "string" && isBlockedMember(key)) {
+          throw new InterpreterRuntimeError(`${objectValue.name}.${key} is not available in CodeMode.`, propertyNode)
         }
+        if (typeof key !== "string") return new ComputedValue(undefined)
         if (objectValue.name === "Math" && mathConstants.has(key)) {
           return new ComputedValue((Math as unknown as Record<string, number>)[key])
         }
-        return new GlobalMethodReference(objectValue.name, key)
+        if (globalStaticMembers[objectValue.name]?.has(key)) {
+          return new GlobalMethodReference(objectValue.name, key)
+        }
+        // Unknown static members read as undefined so feature detection works like native JS.
+        return new ComputedValue(undefined)
       }
 
       if (typeof objectValue === "string") {
@@ -1858,12 +1907,21 @@ export class Interpreter<R> {
         return new ComputedValue(undefined)
       }
 
-      if (objectValue instanceof CoercionFunction && typeof key === "string" && !isBlockedMember(key)) {
+      if (objectValue instanceof CoercionFunction) {
+        if (typeof key === "string" && isBlockedMember(key)) {
+          throw new InterpreterRuntimeError(`${objectValue.name}.${key} is not available in CodeMode.`, propertyNode)
+        }
+        if (typeof key !== "string") return new ComputedValue(undefined)
         if (objectValue.name === "Number" && numberConstants.has(key)) {
           return new ComputedValue((Number as unknown as Record<string, number>)[key])
         }
-        if (objectValue.name === "Number" && numberStatics.has(key)) return new GlobalMethodReference("Number", key)
-        if (objectValue.name === "String" && stringStatics.has(key)) return new GlobalMethodReference("String", key)
+        if (objectValue.name === "Number" && numberStatics.has(key)) {
+          return new GlobalMethodReference("Number", key)
+        }
+        if (objectValue.name === "String" && stringStatics.has(key)) {
+          return new GlobalMethodReference("String", key)
+        }
+        return new ComputedValue(undefined)
       }
 
       if (objectValue instanceof CodeModeDate) {

packages/codemode/src/stdlib/console.ts

@@ -89,7 +89,7 @@ const formatConsoleTable = (value: unknown, columnsArgument: unknown): string =>
 const consoleTableColumns = (value: unknown): ReadonlyArray<string> | undefined => {
   if (value === undefined) return undefined
   if (containsRuntimeReference(value)) return undefined
-  const columns = copyOut(copyIn(value, "console.table columns"), true)
+  const columns = copyOut(copyIn(value, "console.table columns"), "nullify")
   return Array.isArray(columns) ? columns.map((column) => String(column)) : undefined
 }
 

packages/codemode/src/stdlib/date.ts

@@ -23,6 +23,8 @@ export const dateMethods = new Set([
   "getTimezoneOffset",
 ])
 
+export const dateStatics = new Set(["now", "parse", "UTC"])
+
 export const invokeDateStatic = (name: string, args: Array<unknown>, node: AstNode): number => {
   switch (name) {
     case "now":

packages/codemode/src/stdlib/json.ts

@@ -2,6 +2,8 @@ import { type AstNode, InterpreterRuntimeError, supportedSyntaxMessage } from ".
 import { typeofValue } from "../interpreter/references.js"
 import { copyIn, copyOut } from "../tool-runtime.js"
 
+export const jsonStatics = new Set(["parse", "stringify"])
+
 export const invokeJsonMethod = (name: string, args: Array<unknown>, node: AstNode): unknown => {
   switch (name) {
     case "stringify": {
@@ -16,7 +18,7 @@ export const invokeJsonMethod = (name: string, args: Array<unknown>, node: AstNo
       }
       const space = args[2]
       const indent = typeof space === "number" || typeof space === "string" ? space : undefined
-      return JSON.stringify(copyOut(copyIn(args[0], "JSON.stringify value")), null, indent)
+      return JSON.stringify(copyOut(copyIn(args[0], "JSON.stringify value"), "json"), null, indent)
     }
     case "parse": {
       const text = args[0]

packages/codemode/src/stdlib/object.ts

@@ -6,6 +6,8 @@ import { boundedData, coerceToString } from "./value.js"
 
 export const objectMethodsPreservingIdentity = new Set(["assign", "values", "entries", "fromEntries"])
 
+export const objectStatics = new Set(["keys", "values", "entries", "hasOwn", "is", "assign", "fromEntries"])
+
 export const invokeObjectMethod = (name: string, args: Array<unknown>, node: AstNode): unknown => {
   const requireObject = (): Record<string, unknown> => {
     const input = args[0]

packages/codemode/src/stdlib/regexp.ts

@@ -19,6 +19,8 @@ export const escapeRegexHint =
   'To match special characters like ( ) [ ] { } + * ? . literally, escape them with a backslash (e.g. "\\\\(") or test for them with String.includes instead.'
 
 export const toHostRegex = (arg: unknown, method: string, node: AstNode, extraFlags = ""): RegExp => {
+  // Native parity: an undefined pattern behaves as an empty pattern.
+  if (arg === undefined) return new RegExp("", extraFlags)
   if (arg instanceof CodeModeRegExp) return arg.regex
   if (typeof arg === "string") {
     try {

packages/codemode/src/stdlib/value.ts

@@ -61,10 +61,19 @@ export const coerceToString = (value: unknown): string => {
 export const coerceToNumber = (value: unknown): number => {
   if (value instanceof CodeModeDate) return value.time
   if (isCodeModeValue(value)) return Number.NaN
-  return value !== null && typeof value === "object" && !Array.isArray(value) ? Number.NaN : Number(value)
+  // Arrays coerce through our own string coercion: host Number(array) joins with host
+  // ToPrimitive, which throws on the null-prototype objects the interpreter produces.
+  if (Array.isArray(value)) return Number(coerceToString(value))
+  return value !== null && typeof value === "object" ? Number.NaN : Number(value)
 }
 
 export const invokeCoercion = (ref: CoercionFunction, args: Array<unknown>, node: AstNode): unknown => {
+  // Native: Number() is 0 and String() is "", unlike their undefined-argument forms; the
+  // other coercers match native through the undefined-argument path below.
+  if (args.length === 0) {
+    if (ref.name === "Number") return 0
+    if (ref.name === "String") return ""
+  }
   const raw = args[0]
   // Error values are plain SafeObjects; the boundedData path below would strip their brand.
   if (ref.name === "String" && errorBrandName(raw) !== undefined) return coerceToString(raw)
@@ -72,12 +81,16 @@ export const invokeCoercion = (ref: CoercionFunction, args: Array<unknown>, node
     if (ref.name === "Boolean") return true
     if (ref.name === "Number") return coerceToNumber(raw)
     if (ref.name === "String") return coerceToString(raw)
+    if (ref.name === "isFinite") return Number.isFinite(coerceToNumber(raw))
+    if (ref.name === "isNaN") return Number.isNaN(coerceToNumber(raw))
     if (ref.name === "parseInt") return parseInt(coerceToString(raw))
     return parseFloat(coerceToString(raw))
   }
   const value = boundedData(raw, `${ref.name} input`)
   if (ref.name === "Number") return coerceToNumber(value)
   if (ref.name === "Boolean") return Boolean(value)
+  if (ref.name === "isFinite") return Number.isFinite(coerceToNumber(value))
+  if (ref.name === "isNaN") return Number.isNaN(coerceToNumber(value))
   if (ref.name === "parseInt") {
     const radix = args[1]
     if (radix !== undefined && typeof radix !== "number") {

packages/codemode/src/tool-runtime.ts

@@ -118,8 +118,7 @@ export class ToolRuntimeError extends Error {
   }
 }
 
-const isDefinition = <R>(value: Definition<R> | Tools<R>): value is Definition<R> =>
-  isToolDefinition<R>(value)
+const isDefinition = <R>(value: Definition<R> | Tools<R>): value is Definition<R> => isToolDefinition<R>(value)
 
 const runHost = <A, E, R>(effect: Effect.Effect<A, E, R>): Effect.Effect<A, ToolError, R> =>
   effect.pipe(
@@ -257,18 +256,31 @@ const copyBounded = (
   return copied
 }
 
-export const copyOut = (value: unknown, undefinedAsNull = false): unknown => {
-  if (value === undefined && undefinedAsNull) return null
+// "json" mirrors JSON.stringify (undefined object values drop, undefined array elements become
+// null, a bare undefined passes through): use it wherever data leaves as JSON, like tool
+// arguments and stringify-style formatting. "nullify" turns every undefined, including a bare
+// one, into null: use it for program results, where the consumer must never see undefined.
+export type CopyOutMode = "json" | "nullify"
+
+export const copyOut = (value: unknown, mode: CopyOutMode): unknown => {
+  if (value === undefined && mode === "nullify") return null
   if (typeof value === "number" && !Number.isFinite(value)) {
     return null
   }
   if (Array.isArray(value)) {
     // Array.from densifies holes so sparse arrays normalize at the boundary like JSON does.
-    return Array.from(value, (item) => copyOut(item, undefinedAsNull))
+    return Array.from(value, (item) => {
+      const copied = copyOut(item, mode)
+      return copied === undefined && mode === "json" ? null : copied
+    })
   }
 
   if (value !== null && typeof value === "object" && !(value instanceof ToolReference)) {
-    return Object.fromEntries(Object.entries(value).map(([key, item]) => [key, copyOut(item, undefinedAsNull)]))
+    return Object.fromEntries(
+      Object.entries(value)
+        .map(([key, item]) => [key, copyOut(item, mode)] as const)
+        .filter(([, item]) => !(item === undefined && mode === "json")),
+    )
   }
 
   return value
@@ -696,13 +708,13 @@ export const make = <R>(
         invokeDefinition(
           "search",
           searchTool,
-          args.map((arg) => copyOut(copyIn(arg, "Arguments for tool 'search'"))),
+          args.map((arg) => copyOut(copyIn(arg, "Arguments for tool 'search'"), "json")),
         ),
       ),
     invoke: (path, args) =>
       Effect.gen(function* () {
         const name = canonicalSegments(path).join(".")
-        const externalArgs = args.map((arg) => copyOut(copyIn(arg, `Arguments for tool '${name}'`)))
+        const externalArgs = args.map((arg) => copyOut(copyIn(arg, `Arguments for tool '${name}'`), "json"))
         const tool = resolve(root, path)
         return yield* invokeDefinition(name, tool, externalArgs)
       }),

packages/codemode/test/codemode.test.ts

@@ -453,6 +453,56 @@ describe("CodeMode schema flexibility", () => {
     expect(observed).toStrictEqual([{ id: 42 }])
   })
 
+  test("outbound tool arguments follow JSON serialization semantics", async () => {
+    const observed: Array<unknown> = []
+    const call = Tool.make({
+      description: "Observe raw input",
+      input: { type: "object" },
+      run: (input) =>
+        Effect.sync(() => {
+          observed.push(input)
+          return "ok"
+        }),
+    })
+    const runtime = CodeMode.make({ tools: { adapter: { call } } })
+
+    const result = await Effect.runPromise(
+      runtime.execute(
+        `return await tools.adapter.call({ q: undefined, limit: 0 / 0, rate: 1 / 0, items: [1, undefined, 2], holes: [1, , 3] })`,
+      ),
+    )
+    expect(result.ok).toBe(true)
+    const received = observed[0] as Record<string, unknown>
+    expect(received).toStrictEqual({ limit: null, rate: null, items: [1, null, 2], holes: [1, null, 3] })
+    // The undefined-valued property is dropped like JSON.stringify, not delivered as undefined.
+    expect(Object.hasOwn(received, "q")).toBe(false)
+  })
+
+  test("dropping undefined values lets optionalKey schemas accept conditional arguments", async () => {
+    const observed: Array<unknown> = []
+    const find = Tool.make({
+      description: "Find things",
+      input: Schema.Struct({ query: Schema.optionalKey(Schema.String), limit: Schema.optionalKey(Schema.Number) }),
+      run: (input) =>
+        Effect.sync(() => {
+          observed.push(input)
+          return "ok"
+        }),
+    })
+    const runtime = CodeMode.make({ tools: { things: { find } } })
+
+    // The `cond ? value : undefined` idiom: optionalKey rejects a present undefined, so the
+    // JSON boundary must drop the key before the schema decodes.
+    const result = await Effect.runPromise(
+      runtime.execute(`return await tools.things.find({ query: undefined, limit: 5 })`),
+    )
+    expect(result.ok).toBe(true)
+    expect(observed).toStrictEqual([{ limit: 5 }])
+
+    const search = await Effect.runPromise(runtime.execute(`return (await search({ query: undefined })).items.length`))
+    expect(search.ok).toBe(true)
+  })
+
   test("renders JSON Schema outputs and $defs references", async () => {
     const lookup = Tool.make({
       description: "Look up a user",

packages/codemode/test/parity.test.ts

@@ -258,11 +258,23 @@ describe("H1: NaN/Infinity flow as intermediates and normalize to null at the bo
 
   test("copyOut normalizes non-finite numbers to null (the shared return + tool-arg boundary)", () => {
     // Tool-call arguments funnel through copyOut too, so this one function pins both boundaries.
-    expect(ToolRuntime.copyOut(NaN)).toBeNull()
-    expect(ToolRuntime.copyOut(Infinity)).toBeNull()
-    expect(ToolRuntime.copyOut(-Infinity)).toBeNull()
-    expect(ToolRuntime.copyOut(42)).toBe(42)
-    expect(ToolRuntime.copyOut({ a: NaN, b: [Infinity, 1] })).toEqual({ a: null, b: [null, 1] })
+    expect(ToolRuntime.copyOut(NaN, "json")).toBeNull()
+    expect(ToolRuntime.copyOut(Infinity, "json")).toBeNull()
+    expect(ToolRuntime.copyOut(-Infinity, "nullify")).toBeNull()
+    expect(ToolRuntime.copyOut(42, "json")).toBe(42)
+    expect(ToolRuntime.copyOut({ a: NaN, b: [Infinity, 1] }, "json")).toEqual({ a: null, b: [null, 1] })
+  })
+})
+
+describe("copyOut undefined handling per boundary mode", () => {
+  test("json mode mirrors JSON.stringify for undefined", () => {
+    expect(ToolRuntime.copyOut({ q: undefined, keep: 1 }, "json")).toStrictEqual({ keep: 1 })
+    expect(ToolRuntime.copyOut([1, undefined, 2], "json")).toStrictEqual([1, null, 2])
+    expect(ToolRuntime.copyOut({ nested: { a: undefined, b: [undefined] } }, "json")).toStrictEqual({
+      nested: { b: [null] },
+    })
+    expect(ToolRuntime.copyOut(undefined, "json")).toBeUndefined()
+    expect(ToolRuntime.copyOut({ a: undefined }, "nullify")).toStrictEqual({ a: null })
   })
 })
 
@@ -669,3 +681,177 @@ describe("destructuring assignment", () => {
     expect(err.message).toContain("Property key must be a string or number")
   })
 })
+
+describe("coercion parity: zero-argument coercion functions", () => {
+  test("Number() is 0 and String() is empty, unlike their undefined-argument forms", async () => {
+    expect(await value(`return Number()`)).toBe(0)
+    expect(await value(`return String()`)).toBe("")
+    expect(await value(`return Boolean()`)).toBe(false)
+    expect(await value(`return Number.isNaN(Number(undefined))`)).toBe(true)
+    expect(await value(`return String(undefined)`)).toBe("undefined")
+  })
+
+  test("parseInt() and parseFloat() stay NaN with no argument", async () => {
+    expect(await value(`return Number.isNaN(parseInt())`)).toBe(true)
+    expect(await value(`return Number.isNaN(parseFloat())`)).toBe(true)
+  })
+})
+
+describe("coercion parity: global isFinite and isNaN", () => {
+  test("coerce their argument like native JS, unlike the Number statics", async () => {
+    expect(await value(`return isFinite("42")`)).toBe(true)
+    expect(await value(`return Number.isFinite("42")`)).toBe(false)
+    expect(await value(`return isNaN("oops")`)).toBe(true)
+    expect(await value(`return isNaN("42")`)).toBe(false)
+    expect(await value(`return isFinite(Infinity)`)).toBe(false)
+    expect(await value(`return isNaN(null)`)).toBe(false)
+  })
+
+  test("zero-argument forms match native", async () => {
+    expect(await value(`return isFinite()`)).toBe(false)
+    expect(await value(`return isNaN()`)).toBe(true)
+  })
+
+  test("read as functions", async () => {
+    expect(await value(`return typeof isFinite`)).toBe("function")
+    expect(await value(`return typeof isNaN`)).toBe("function")
+  })
+
+  test("work as array callbacks", async () => {
+    expect(await value(`return [1, "2", "x", Infinity].filter(isFinite)`)).toEqual([1, "2"])
+    expect(await value(`return ["1", "x"].map(isNaN)`)).toEqual([false, true])
+  })
+})
+
+describe("coercion parity: arrays coerce to numbers through their string form", () => {
+  test("arrays with objects become NaN instead of crashing on host ToPrimitive", async () => {
+    expect(await value(`let x = [{}]; x++; return Number.isNaN(x)`)).toBe(true)
+    expect(await value(`return isFinite([{}])`)).toBe(false)
+    expect(await value(`return "abc".slice([{}])`)).toBe("abc")
+  })
+
+  test("single-element and empty arrays match native Number()", async () => {
+    expect(await value(`return Number([5])`)).toBe(5)
+    expect(await value(`return Number([])`)).toBe(0)
+    expect(await value(`return Number.isNaN(Number([1, 2]))`)).toBe(true)
+  })
+})
+
+describe("coercion parity: String method arguments coerce like native JS", () => {
+  test("includes and indexOf coerce numbers", async () => {
+    expect(await value(`return "v1.2".includes(1)`)).toBe(true)
+    expect(await value(`return "a2b".indexOf(2)`)).toBe(1)
+    expect(await value(`return "abc".includes("d")`)).toBe(false)
+  })
+
+  test("slice, repeat, and padStart coerce numeric strings", async () => {
+    expect(await value(`return "abc".slice("1")`)).toBe("bc")
+    expect(await value(`return "ab".repeat("2")`)).toBe("abab")
+    expect(await value(`return "7".padStart("3", 0)`)).toBe("007")
+  })
+
+  test("split coerces separators but treats undefined as absent", async () => {
+    expect(await value(`return "a1b".split(1)`)).toEqual(["a", "b"])
+    expect(await value(`return "a,b".split(undefined)`)).toEqual(["a,b"])
+    expect(await value(`return "a,b".split()`)).toEqual(["a,b"])
+    expect(await value(`return "a,b".split(undefined, 0)`)).toEqual([])
+    expect(await value(`return "a,b".split(undefined, 1)`)).toEqual(["a,b"])
+  })
+
+  test("replace coerces search and replacement values", async () => {
+    expect(await value(`return "a1b".replace(1, 2)`)).toBe("a2b")
+    expect(await value(`return "a1b".replace(1, () => "x")`)).toBe("axb")
+  })
+
+  test("repeat rejections carry the native RangeError name", async () => {
+    expect(await value(`try { "a".repeat(-1) } catch (e) { return e.name }`)).toBe("RangeError")
+  })
+
+  test("includes, startsWith, and endsWith reject regular expressions with a TypeError", async () => {
+    expect(await value(`try { "abc".includes(/a/) } catch (e) { return e.name }`)).toBe("TypeError")
+    expect(await value(`try { "abc".startsWith(/a/) } catch (e) { return e.name }`)).toBe("TypeError")
+    expect(await value(`try { "abc".endsWith(/a/) } catch (e) { return e.name }`)).toBe("TypeError")
+  })
+
+  test("opaque runtime references still reject as data errors", async () => {
+    const err = await error(`const f = () => 1; return "abc".includes(f)`)
+    expect(err.message).toContain("data value")
+    const replacerErr = await error(`const f = () => 1; return "a".replace(f, () => "x")`)
+    expect(replacerErr.message).toContain("data value")
+  })
+})
+
+describe("coercion parity: match() and search() with no argument", () => {
+  test("behave as an empty pattern like native JS", async () => {
+    expect(await value(`return "abc".search()`)).toBe(0)
+    expect(await value(`const m = "abc".match(); return { first: m[0], index: m.index }`)).toEqual({
+      first: "",
+      index: 0,
+    })
+  })
+})
+
+describe("coercion parity: ++ and -- use CodeMode numeric coercion", () => {
+  test("numeric strings increment like native JS", async () => {
+    expect(await value(`let x = "5"; x++; return x`)).toBe(6)
+    expect(await value(`let x = "5"; return ++x`)).toBe(6)
+    expect(await value(`const o = { n: "2" }; o.n--; return o.n`)).toBe(1)
+  })
+
+  test("dates increment through their epoch time", async () => {
+    expect(await value(`let d = new Date(5); d++; return d`)).toBe(6)
+  })
+
+  test("plain data objects become NaN instead of crashing", async () => {
+    expect(await value(`let x = {}; x++; return Number.isNaN(x)`)).toBe(true)
+    expect(await value(`const o = { a: {} }; o.a++; return Number.isNaN(o.a)`)).toBe(true)
+  })
+
+  test("opaque runtime references reject with a clear error", async () => {
+    const err = await error(`let f = () => 1; f++`)
+    expect(err.message).toContain("data value")
+  })
+})
+
+describe("coercion parity: unknown static members read as undefined", () => {
+  test("feature detection on missing statics works like native JS", async () => {
+    expect(await value(`return typeof Math.sumPrecise`)).toBe("undefined")
+    expect(await value(`return Object.groupBy === undefined`)).toBe(true)
+    expect(await value(`return RegExp.escape === undefined`)).toBe(true)
+    expect(await value(`return Number.range === undefined`)).toBe(true)
+    expect(await value(`return String.raw === undefined`)).toBe(true)
+    expect(await value(`return isFinite.something === undefined`)).toBe(true)
+    expect(await value(`return console.group === undefined`)).toBe(true)
+    expect(await value(`return Date.moment === undefined`)).toBe(true)
+    expect(await value(`return JSON.rawJSON === undefined`)).toBe(true)
+    expect(await value(`return URL.createObjectURL === undefined`)).toBe(true)
+    expect(await value(`return Map.groupBy === undefined`)).toBe(true)
+    expect(await value(`return Math.sumPrecise?.([1]) ?? "fallback"`)).toBe("fallback")
+  })
+
+  test("known statics still resolve and run", async () => {
+    expect(await value(`return typeof Math.max`)).toBe("function")
+    expect(await value(`return typeof console.log`)).toBe("function")
+    expect(await value(`return typeof Date.now`)).toBe("function")
+    expect(await value(`return Math.max(1, 2)`)).toBe(2)
+    expect(await value(`return URL.canParse("https://example.com")`)).toBe(true)
+    expect(await value(`return Number.isInteger(3)`)).toBe(true)
+    expect(await value(`return Number.MAX_SAFE_INTEGER`)).toBe(Number.MAX_SAFE_INTEGER)
+  })
+
+  test("calling an unknown static reports a native-style TypeError", async () => {
+    expect(await value(`try { Math.sumPrecise([1]) } catch (e) { return e.name + ": " + e.message }`)).toBe(
+      "TypeError: Math.sumPrecise is not a function.",
+    )
+    expect(await value(`try { Math["sumPrecise"]([1]) } catch (e) { return e.message }`)).toBe(
+      "Math.sumPrecise is not a function.",
+    )
+  })
+
+  test("blocked members still throw instead of reading as undefined", async () => {
+    const err = await error(`return Math.constructor`)
+    expect(err.message).toContain("not available")
+    const coercionErr = await error(`return Number.constructor`)
+    expect(coercionErr.message).toContain("Number.constructor is not available")
+  })
+})

packages/core/src/aisdk.ts

@@ -30,6 +30,7 @@ import {
   type UsageInput,
 } from "@opencode-ai/ai"
 import { Auth, Endpoint, type AnyRoute } from "@opencode-ai/ai/route"
+import { ProviderShared } from "@opencode-ai/ai/protocols/shared"
 import { Cause, Context, Effect, Layer, Option, Schema, Scope, Stream } from "effect"
 import { ModelV2 } from "./model"
 import { ProviderV2 } from "./provider"
@@ -605,6 +606,7 @@ function streamPartEvents(
         LLMEvent.toolInputStart({
           id: event.id,
           name: event.toolName,
+          providerExecuted: event.providerExecuted,
           providerMetadata: providerMetadata(event.providerMetadata),
         }),
       ])
@@ -622,15 +624,30 @@ function streamPartEvents(
       ])
     case "tool-call":
       state.toolNames[event.toolCallId] = event.toolName
-      return Effect.succeed([
-        LLMEvent.toolCall({
-          id: event.toolCallId,
-          name: event.toolName,
-          input: parseToolInput(event.input),
-          providerExecuted: event.providerExecuted,
-          providerMetadata: providerMetadata(event.providerMetadata),
-        }),
-      ])
+      return ProviderShared.parseToolInput("aisdk", event.toolName, event.input).pipe(
+        Effect.map((input) => [
+          LLMEvent.toolCall({
+            id: event.toolCallId,
+            name: event.toolName,
+            input,
+            providerExecuted: event.providerExecuted,
+            providerMetadata: providerMetadata(event.providerMetadata),
+          }),
+        ]),
+        Effect.catch((error) =>
+          event.providerExecuted
+            ? Effect.fail(error)
+            : Effect.succeed([
+                LLMEvent.toolInputError({
+                  id: event.toolCallId,
+                  name: event.toolName,
+                  raw: event.input,
+                  message: error.reason.message,
+                  providerMetadata: providerMetadata(event.providerMetadata),
+                }),
+              ]),
+        ),
+      )
     case "tool-result":
       delete state.toolNames[event.toolCallId]
       return Effect.succeed([
@@ -685,14 +702,6 @@ function providerMetadata(value: unknown) {
   return Schema.is(ProviderMetadata)(value) ? value : undefined
 }
 
-function parseToolInput(value: string) {
-  try {
-    return JSON.parse(value) as unknown
-  } catch {
-    return value
-  }
-}
-
 function jsonObject(input: Record<string, unknown>) {
   return Object.fromEntries(Object.entries(input).map(([key, value]) => [key, jsonValue(value)]))
 }

packages/core/src/config/mcp.ts

@@ -23,6 +23,9 @@ export class Local extends Schema.Class<Local>("ConfigV2.MCP.Local")({
   }),
   environment: Schema.Record(Schema.String, Schema.String).pipe(Schema.optional),
   disabled: Schema.Boolean.pipe(Schema.optional),
+  codemode: Schema.Boolean.pipe(Schema.optional).annotate({
+    description: "Expose this server's tools through Code Mode. Defaults to true.",
+  }),
   timeout: Timeout.pipe(Schema.optional),
 }) {}
 
@@ -40,6 +43,9 @@ export class Remote extends Schema.Class<Remote>("ConfigV2.MCP.Remote")({
   headers: Schema.Record(Schema.String, Schema.String).pipe(Schema.optional),
   oauth: Schema.Union([OAuth, Schema.Literal(false)]).pipe(Schema.optional),
   disabled: Schema.Boolean.pipe(Schema.optional),
+  codemode: Schema.Boolean.pipe(Schema.optional).annotate({
+    description: "Expose this server's tools through Code Mode. Defaults to true.",
+  }),
   timeout: Timeout.pipe(Schema.optional),
 }) {}
 

packages/core/src/effect/layer-node.ts

@@ -74,7 +74,7 @@ type MakeInput<
   T extends Tag | undefined = undefined,
 > = NodeIdentity & {
   readonly layer: Implementation
-  readonly deps: (Items | (() => Items)) & CheckDependencies<Implementation, NoInfer<Items>>
+  readonly deps: Items & CheckDependencies<Implementation, NoInfer<Items>>
   readonly tag?: T
 }
 
@@ -90,9 +90,7 @@ export function make<
     name: input.service !== undefined ? input.service.key : input.name,
     service: input.service,
     implementation: input.layer,
-    get dependencies() {
-      return typeof input.deps === "function" ? input.deps() : input.deps
-    },
+    dependencies: input.deps,
     tag: input.tag,
   }
 }

packages/core/src/location-mutation.ts

@@ -12,8 +12,8 @@ export const Kind = Schema.Literals(["file", "directory"])
 export type Kind = typeof Kind.Type
 
 /**
- * Mutation paths do not accept project references. Relative paths must stay
- * inside the active Location. Absolute paths outside it require separate
+ * Mutation paths do not accept project references. Relative paths resolve
+ * from the active Location. Paths outside it require separate
  * `external_directory` approval.
  */
 export const ResolveInput = Schema.Struct({
@@ -25,7 +25,7 @@ export type ResolveInput = typeof ResolveInput.Type
 
 export class PathError extends Schema.TaggedErrorClass<PathError>()("LocationMutation.PathError", {
   path: Schema.String,
-  reason: Schema.Literals(["relative_escape", "location_escape", "non_directory_ancestor"]),
+  reason: Schema.Literals(["location_escape", "non_directory_ancestor"]),
 }) {}
 
 export interface ExternalDirectoryAuthorization {
@@ -53,9 +53,9 @@ export interface Target {
 
 export interface Interface {
   /**
-   * Resolve a path and derive its permission resources. Relative paths must
-   * stay inside the Location. Absolute paths outside it require separate
-   * `external_directory` approval. This does not approve the mutation.
+   * Resolve a path and derive its permission resources. Relative paths resolve
+   * from the Location. Paths outside it require separate `external_directory`
+   * approval. This does not approve the mutation.
    */
   readonly resolve: (input: ResolveInput) => Effect.Effect<Target, PathError | FSUtil.Error>
 }
@@ -120,10 +120,8 @@ const layer = Layer.effect(
     })
 
     const resolve = Effect.fn("LocationMutation.resolve")(function* (input: ResolveInput) {
-      const relative = !path.isAbsolute(input.path)
       const absolute = path.resolve(location.directory, input.path)
       const lexicallyInternal = FSUtil.contains(location.directory, absolute)
-      if (relative && !lexicallyInternal) return yield* new PathError({ path: input.path, reason: "relative_escape" })
 
       const resolved = yield* resolvePath(absolute)
       if (lexicallyInternal && !FSUtil.contains(locationRoot, resolved.canonical)) {
@@ -146,10 +144,7 @@ const layer = Layer.effect(
               directory: externalDirectory,
               resource: externalResource,
               save: slash(
-                path.join(
-                  (yield* Project.root(fs, AbsolutePath.make(externalDirectory))) ?? externalDirectory,
-                  "*",
-                ),
+                path.join((yield* Project.root(fs, AbsolutePath.make(externalDirectory))) ?? externalDirectory, "*"),
               ),
             }
           : undefined,

packages/core/src/mcp/index.ts

@@ -13,8 +13,10 @@ import { EventV2 } from "../event"
 import { Form } from "../form"
 import { Integration } from "../integration"
 import { IntegrationConnection } from "../integration/connection"
+import { KeyedMutex } from "../effect/keyed-mutex"
 import { Location } from "../location"
 import { waitForAbort } from "../process"
+import { State } from "../state"
 import { MCPClient } from "./client"
 import { MCPOAuth } from "./oauth"
 
@@ -40,6 +42,7 @@ export class ServerInstructions extends Schema.Class<ServerInstructions>("MCP.Se
 export class Tool extends Schema.Class<Tool>("MCP.Tool")({
   server: ServerName,
   name: Schema.String,
+  codemode: Schema.Boolean.pipe(Schema.optional),
   description: Schema.String.pipe(Schema.optional),
   inputSchema: Schema.Unknown.pipe(Schema.optional),
   outputSchema: Schema.Unknown.pipe(Schema.optional),
@@ -118,6 +121,7 @@ type ServerEntry = {
   prompts?: ReadonlyArray<Prompt>
   // Set when a remote server is registered as an OAuth integration; the credential lives in the global store.
   integrationID?: Integration.ID
+  registration?: State.Registration
 }
 
 // MCP elicitations are Location-scoped, not Session-scoped: the server cannot attribute them to a
@@ -127,6 +131,10 @@ const URL_ELICITATION_FIELD_KEY = "elicitation"
 
 export interface Interface {
   readonly servers: () => Effect.Effect<ServerInfo[]>
+  readonly add: (server: ServerName | string, config: typeof ConfigMCP.Server.Type) => Effect.Effect<void>
+  readonly connect: (server: ServerName | string) => Effect.Effect<void, NotFoundError>
+  readonly disconnect: (server: ServerName | string) => Effect.Effect<void, NotFoundError>
+  readonly remove: (server: ServerName | string) => Effect.Effect<void, NotFoundError>
   readonly tools: () => Effect.Effect<Tool[]>
   readonly callTool: (input: {
     readonly server: ServerName | string
@@ -170,6 +178,9 @@ export const layer = Layer.effect(
     )
     // Later config files win for duplicate server names; per-server timeout overrides globals.
     const runtime = new Map<ServerName, ServerEntry>()
+    // Serializes lifecycle operations per server. Anything taking this lock from a connection
+    // callback must stay forked: lifecycle operations close scopes while holding it, firing onClose.
+    const locks = KeyedMutex.makeUnsafe<ServerName>()
     const urlElicitations = new Map<string, Form.ID>()
     for (const entry of documents) {
       for (const [name, server] of Object.entries(entry.info.mcp?.servers ?? {})) {
@@ -183,14 +194,9 @@ export const layer = Layer.effect(
 
     // Register every remote server as an OAuth integration so credentials live in the global store
     // rather than in committed config. Servers that connect anonymously simply never use the method.
-    const registrations: Array<{
-      readonly name: ServerName
-      readonly remote: typeof ConfigMCP.Remote.Type
-      readonly integrationID: Integration.ID
-      readonly methodID: Integration.MethodID
-    }> = []
-    for (const [name, entry] of runtime) {
-      if (entry.config.type !== "remote" || entry.config.oauth === false) continue
+    const owned = new Set<Integration.ID>()
+    const register = Effect.fnUntraced(function* (name: ServerName, entry: ServerEntry) {
+      if (entry.config.type !== "remote" || entry.config.oauth === false) return
       const remote = entry.config
       // Key identity on name + url, not url alone: two configs for the same url under different names are
       // distinct logical servers that may hold different accounts, so they must not share a credential row.
@@ -200,27 +206,24 @@ export const layer = Layer.effect(
           .update(name + "\u0000" + remote.url)
           .digest("hex")
           .slice(0, 16)
-      entry.integrationID = Integration.ID.make(suffix)
-      registrations.push({
-        name,
-        remote,
-        integrationID: entry.integrationID,
-        methodID: Integration.MethodID.make(suffix),
-      })
-    }
-    if (registrations.length > 0)
-      yield* integration.transform((draft) => {
-        for (const reg of registrations) {
-          draft.update(reg.integrationID, (ref) => {
-            ref.name = reg.name
+      const integrationID = Integration.ID.make(suffix)
+      entry.integrationID = integrationID
+      owned.add(integrationID)
+      const methodID = Integration.MethodID.make(suffix)
+      entry.registration = yield* integration
+        .transform((draft) => {
+          draft.update(integrationID, (ref) => {
+            ref.name = name
           })
           draft.method.update({
-            integrationID: reg.integrationID,
-            method: { id: reg.methodID, type: "oauth", label: reg.name },
-            authorize: () => MCPOAuth.authorize({ name: reg.name, config: reg.remote, methodID: reg.methodID }),
+            integrationID,
+            method: { id: methodID, type: "oauth", label: name },
+            authorize: () => MCPOAuth.authorize({ name, config: remote, methodID }),
           })
-        }
-      })
+        })
+        .pipe(Scope.provide(root))
+    })
+    yield* Effect.forEach(runtime, ([name, entry]) => register(name, entry), { discard: true })
 
     const requireServer = Effect.fnUntraced(function* (server: ServerName | string) {
       const name = ServerName.make(server)
@@ -360,10 +363,11 @@ export const layer = Layer.effect(
         }),
     } satisfies MCPClient.ElicitationHandler
 
-    const toTool = (server: ServerName, def: MCPClient.ToolDefinition) =>
+    const toTool = (server: ServerName, entry: ServerEntry, def: MCPClient.ToolDefinition) =>
       new Tool({
         server,
         name: def.name,
+        codemode: entry.config.codemode,
         description: def.description,
         inputSchema: def.inputSchema,
         outputSchema: def.outputSchema,
@@ -405,7 +409,7 @@ export const layer = Layer.effect(
     const refreshTools = (name: ServerName, entry: ServerEntry, connection: MCPClient.Connection) =>
       connection.tools().pipe(
         Effect.map((defs) => {
-          entry.tools = defs.map((def) => toTool(name, def))
+          entry.tools = defs.map((def) => toTool(name, entry, def))
         }),
       )
 
@@ -420,36 +424,44 @@ export const layer = Layer.effect(
         ),
       )
 
-    const watch = (name: ServerName, entry: ServerEntry, connection: MCPClient.Connection) => {
-      connection.onClose(() => {
-        // A reconnect closes the previous scope, but the SDK may fire this onclose after the new
-        // connection is already assigned; ignore the stale close so it can't null out the live client.
-        if (entry.client !== connection) return
-        entry.client = undefined
-        entry.tools = undefined
-        entry.prompts = undefined
-        entry.status = { status: "failed", error: "Connection closed" }
-        fork(events.publish(McpEvent.ToolsChanged, { server: name }).pipe(Effect.ignore))
-        fork(events.publish(McpEvent.ResourcesChanged, { server: name }).pipe(Effect.ignore))
-        fork(events.publish(Command.Event.Updated, {}).pipe(Effect.ignore))
-        fork(events.publish(McpEvent.StatusChanged, { server: name }).pipe(Effect.ignore))
-      })
-      connection.onLog((message) => fork(serverLog(name, message).pipe(Effect.ignore)))
-      connection.onToolsChanged(() => {
+    // Runs a connection callback under the server lock, dropping it if the connection is no longer
+    // the entry's live client, so late SDK callbacks cannot commit obsolete state.
+    const whenLive =
+      (name: ServerName, entry: ServerEntry, connection: MCPClient.Connection) =>
+      <E>(effect: Effect.Effect<void, E>) =>
         fork(
-          refreshTools(name, entry, connection).pipe(
-            Effect.andThen(events.publish(McpEvent.ToolsChanged, { server: name })),
+          Effect.suspend(() => (entry.client === connection ? effect : Effect.void)).pipe(
+            locks.withLock(name),
             Effect.ignore,
           ),
         )
-      })
-      connection.onPromptsChanged(() => {
-        fork(refreshPrompts(name, entry, connection).pipe(Effect.ignore))
-      })
-      connection.onResourcesChanged(() => {
-        if (entry.client !== connection) return
-        fork(events.publish(McpEvent.ResourcesChanged, { server: name }).pipe(Effect.ignore))
-      })
+
+    const watch = (name: ServerName, entry: ServerEntry, connection: MCPClient.Connection) => {
+      const live = whenLive(name, entry, connection)
+      connection.onClose(() =>
+        live(
+          Effect.gen(function* () {
+            entry.client = undefined
+            entry.tools = undefined
+            entry.prompts = undefined
+            entry.status = { status: "failed", error: "Connection closed" }
+            yield* events.publish(McpEvent.ToolsChanged, { server: name }).pipe(Effect.ignore)
+            yield* events.publish(McpEvent.ResourcesChanged, { server: name }).pipe(Effect.ignore)
+            yield* events.publish(Command.Event.Updated, {}).pipe(Effect.ignore)
+            yield* events.publish(McpEvent.StatusChanged, { server: name }).pipe(Effect.ignore)
+          }),
+        ),
+      )
+      connection.onLog((message) => fork(serverLog(name, message).pipe(Effect.ignore)))
+      connection.onToolsChanged(() =>
+        live(
+          refreshTools(name, entry, connection).pipe(
+            Effect.andThen(events.publish(McpEvent.ToolsChanged, { server: name })),
+          ),
+        ),
+      )
+      connection.onPromptsChanged(() => live(refreshPrompts(name, entry, connection)))
+      connection.onResourcesChanged(() => live(events.publish(McpEvent.ResourcesChanged, { server: name })))
     }
 
     const serverLog = (server: ServerName, message: MCPClient.LogMessage) => {
@@ -472,6 +484,10 @@ export const layer = Layer.effect(
 
     const startServer = (name: ServerName, entry: ServerEntry) =>
       Effect.gen(function* () {
+        // Announce the handshake so connect() and credential reconnects don't show a stale
+        // disabled/failed status for the duration of the connection attempt.
+        entry.status = { status: "pending" }
+        yield* events.publish(McpEvent.StatusChanged, { server: name }).pipe(Effect.ignore)
         const scope = yield* Scope.fork(root)
         entry.scope = scope
         const authProvider = yield* connectProvider(entry)
@@ -484,7 +500,7 @@ export const layer = Layer.effect(
         )
         if (Exit.isSuccess(result)) {
           entry.client = result.value.connection
-          entry.tools = result.value.tools.map((def) => toTool(name, def))
+          entry.tools = result.value.tools.map((def) => toTool(name, entry, def))
           entry.prompts = []
           entry.status = { status: "connected" }
           watch(name, entry, result.value.connection)
@@ -495,7 +511,7 @@ export const layer = Layer.effect(
           yield* events.publish(McpEvent.ToolsChanged, { server: name }).pipe(Effect.ignore)
           yield* events.publish(McpEvent.ResourcesChanged, { server: name }).pipe(Effect.ignore)
           yield* events.publish(McpEvent.StatusChanged, { server: name }).pipe(Effect.ignore)
-          fork(refreshPrompts(name, entry, result.value.connection).pipe(Effect.ignore))
+          whenLive(name, entry, result.value.connection)(refreshPrompts(name, entry, result.value.connection))
           return
         }
         yield* Scope.close(scope, Exit.void)
@@ -509,6 +525,19 @@ export const layer = Layer.effect(
         yield* events.publish(McpEvent.StatusChanged, { server: name }).pipe(Effect.ignore)
       }).pipe(Effect.ensuring(Deferred.succeed(entry.startup, undefined)))
 
+    const stopServer = Effect.fnUntraced(function* (name: ServerName, entry: ServerEntry) {
+      const scope = entry.scope
+      if (!scope) return
+      entry.scope = undefined
+      entry.client = undefined
+      entry.tools = undefined
+      entry.prompts = undefined
+      yield* Scope.close(scope, Exit.void)
+      yield* events.publish(McpEvent.ToolsChanged, { server: name }).pipe(Effect.ignore)
+      yield* events.publish(McpEvent.ResourcesChanged, { server: name }).pipe(Effect.ignore)
+      yield* events.publish(Command.Event.Updated, {}).pipe(Effect.ignore)
+    })
+
     // Disabled servers settle their startup immediately so queries never block on them.
     for (const [name, entry] of runtime) {
       if (entry.config.disabled) {
@@ -516,27 +545,24 @@ export const layer = Layer.effect(
         Deferred.doneUnsafe(entry.startup, Exit.void)
         continue
       }
-      fork(startServer(name, entry))
+      fork(startServer(name, entry).pipe(locks.withLock(name)))
     }
 
     // Bring a server online (or back to needs_auth) when its integration's credential changes, so an
     // OAuth login takes effect without a restart. Only fires for the integrations we registered.
-    const owned = new Set(registrations.map((reg) => reg.integrationID))
     const reconnect = (integrationID: Integration.ID) =>
       Effect.gen(function* () {
         const match = Array.from(runtime).find(([, entry]) => entry.integrationID === integrationID)
         if (!match) return
-        const [name, entry] = match
-        if (entry.config.disabled) return
-        if (entry.scope) {
-          yield* Scope.close(entry.scope, Exit.void)
-          entry.scope = undefined
-          entry.client = undefined
-          entry.tools = undefined
-          entry.prompts = undefined
-          yield* events.publish(Command.Event.Updated, {}).pipe(Effect.ignore)
-        }
-        yield* startServer(name, entry)
+        const name = match[0]
+        yield* Effect.gen(function* () {
+          // add() or remove() may have replaced or deleted the entry while we waited for the lock.
+          const entry = runtime.get(name)
+          if (!entry || entry.integrationID !== integrationID) return
+          if (entry.status.status === "disabled") return
+          yield* stopServer(name, entry)
+          yield* startServer(name, entry)
+        }).pipe(locks.withLock(name))
       })
     fork(
       events.subscribe(Integration.Event.ConnectionUpdated).pipe(
@@ -546,10 +572,13 @@ export const layer = Layer.effect(
       ),
     )
 
-    const whenAllReady = Effect.forEach(runtime.values(), (entry) => Deferred.await(entry.startup), {
-      concurrency: "unbounded",
-      discard: true,
-    })
+    // Suspend so each await sees current entries; a bare Map iterator is exhausted after one run.
+    const whenAllReady = Effect.suspend(() =>
+      Effect.forEach(Array.from(runtime.values()), (entry) => Deferred.await(entry.startup), {
+        concurrency: "unbounded",
+        discard: true,
+      }),
+    )
     return Service.of({
       servers: Effect.fn("MCP.servers")(function* () {
         const entries = Array.from(runtime).toSorted(([a], [b]) => a.localeCompare(b))
@@ -562,6 +591,66 @@ export const layer = Layer.effect(
           }),
         )
       }),
+      add: Effect.fn("MCP.add")(function* (server, config) {
+        const name = ServerName.make(server)
+        yield* Effect.gen(function* () {
+          const previous = runtime.get(name)
+          if (previous) {
+            yield* stopServer(name, previous)
+            if (previous.integrationID) owned.delete(previous.integrationID)
+            if (previous.registration) yield* previous.registration.dispose
+          }
+          const entry: ServerEntry = {
+            config: { ...config, timeout: { ...timeout, ...config.timeout } },
+            status: { status: "pending" },
+            startup: Deferred.makeUnsafe<void>(),
+          }
+          runtime.set(name, entry)
+          yield* Effect.gen(function* () {
+            yield* register(name, entry)
+            if (config.disabled) {
+              entry.status = { status: "disabled" }
+              yield* events.publish(McpEvent.StatusChanged, { server: name }).pipe(Effect.ignore)
+              return
+            }
+            yield* startServer(name, entry)
+          }).pipe(
+            // Settle startup even when register fails or add is interrupted, so an entry that made it
+            // into runtime can never hang readers awaiting its startup.
+            Effect.ensuring(Effect.sync(() => Deferred.doneUnsafe(entry.startup, Exit.void))),
+          )
+        }).pipe(locks.withLock(name))
+      }),
+      connect: Effect.fn("MCP.connect")(function* (server) {
+        const name = ServerName.make(server)
+        yield* Effect.gen(function* () {
+          const target = yield* requireServer(name)
+          yield* stopServer(name, target.entry)
+          yield* startServer(name, target.entry)
+        }).pipe(locks.withLock(name))
+      }),
+      disconnect: Effect.fn("MCP.disconnect")(function* (server) {
+        const name = ServerName.make(server)
+        yield* Effect.gen(function* () {
+          const target = yield* requireServer(name)
+          yield* stopServer(name, target.entry)
+          target.entry.status = { status: "disabled" }
+          yield* events.publish(McpEvent.StatusChanged, { server: name }).pipe(Effect.ignore)
+        }).pipe(locks.withLock(name))
+      }),
+      remove: Effect.fn("MCP.remove")(function* (server) {
+        const name = ServerName.make(server)
+        yield* Effect.gen(function* () {
+          const target = yield* requireServer(name)
+          yield* stopServer(name, target.entry)
+          if (target.entry.integrationID) owned.delete(target.entry.integrationID)
+          if (target.entry.registration) yield* target.entry.registration.dispose
+          // Credentials are kept: they are keyed by name + url, so re-adding the same server
+          // reuses them without forcing re-auth, matching add()'s replacement semantics.
+          runtime.delete(name)
+          yield* events.publish(McpEvent.StatusChanged, { server: name }).pipe(Effect.ignore)
+        }).pipe(locks.withLock(name))
+      }),
       tools: Effect.fn("MCP.tools")(function* () {
         yield* whenAllReady
         return Array.from(runtime.values())

packages/core/src/permission.ts

@@ -6,7 +6,8 @@ import { Permission } from "@opencode-ai/schema/permission"
 import { EventV2 } from "./event"
 import { Location } from "./location"
 import { AgentV2 } from "./agent"
-import { SessionV2 } from "./session"
+import { SessionErrors } from "./session/error"
+import { SessionSchema } from "./session/schema"
 import { SessionStore } from "./session/store"
 import { Wildcard } from "./util/wildcard"
 import { PermissionSaved } from "./permission/saved"
@@ -98,11 +99,11 @@ export function merge(...rulesets: Permission.Ruleset[]): Permission.Ruleset {
 }
 
 export interface Interface {
-  readonly ask: (input: AssertInput) => Effect.Effect<AskResult, SessionV2.NotFoundError>
-  readonly assert: (input: AssertInput) => Effect.Effect<void, Error | SessionV2.NotFoundError>
+  readonly ask: (input: AssertInput) => Effect.Effect<AskResult, SessionErrors.NotFoundError>
+  readonly assert: (input: AssertInput) => Effect.Effect<void, Error | SessionErrors.NotFoundError>
   readonly reply: (input: ReplyInput) => Effect.Effect<void, NotFoundError>
   readonly get: (id: ID) => Effect.Effect<Request | undefined>
-  readonly forSession: (sessionID: SessionV2.ID) => Effect.Effect<ReadonlyArray<Request>>
+  readonly forSession: (sessionID: SessionSchema.ID) => Effect.Effect<ReadonlyArray<Request>>
   readonly list: () => Effect.Effect<ReadonlyArray<Request>>
 }
 
@@ -142,9 +143,12 @@ const layer = Layer.effect(
       )
     })
 
-    const configured = Effect.fn("PermissionV2.configured")(function* (sessionID: SessionV2.ID, agentID?: AgentV2.ID) {
+    const configured = Effect.fn("PermissionV2.configured")(function* (
+      sessionID: SessionSchema.ID,
+      agentID?: AgentV2.ID,
+    ) {
       const session = yield* sessions.get(sessionID)
-      if (!session) return yield* new SessionV2.NotFoundError({ sessionID })
+      if (!session) return yield* new SessionErrors.NotFoundError({ sessionID })
       const agent = yield* agents.resolve(agentID ?? session.agent)
       return agent?.permissions ?? missingAgentPermissions
     })
@@ -301,7 +305,7 @@ const layer = Layer.effect(
       return pending.get(id)?.request
     })
 
-    const forSession = Effect.fn("PermissionV2.forSession")(function* (sessionID: SessionV2.ID) {
+    const forSession = Effect.fn("PermissionV2.forSession")(function* (sessionID: SessionSchema.ID) {
       return Array.from(pending.values(), (item) => item.request).filter((request) => request.sessionID === sessionID)
     })
 

packages/core/src/session.ts

@@ -28,9 +28,9 @@ import { fromRow } from "./session/info"
 import { SessionRunner } from "./session/runner/index"
 import { SessionStore } from "./session/store"
 import { SessionExecution } from "./session/execution"
+import { MessageDecodeError, NotFoundError } from "./session/error"
 import { makeGlobalNode } from "./effect/app-node"
 import { LocationServiceMap } from "./location-service-map"
-import { MessageDecodeError } from "./session/error"
 import { SessionEvent } from "./session/event"
 import { SessionPending } from "./session/pending"
 import { SessionGenerate } from "./session/generate"
@@ -108,10 +108,6 @@ type ForkInput = {
   messageID?: SessionMessage.ID
 }
 
-export class NotFoundError extends Schema.TaggedErrorClass<NotFoundError>()("Session.NotFoundError", {
-  sessionID: SessionSchema.ID,
-}) {}
-
 export class OperationUnavailableError extends Schema.TaggedErrorClass<OperationUnavailableError>()(
   "Session.OperationUnavailableError",
   {
@@ -119,7 +115,7 @@ export class OperationUnavailableError extends Schema.TaggedErrorClass<Operation
   },
 ) {}
 
-export { MessageDecodeError } from "./session/error"
+export { MessageDecodeError, NotFoundError }
 
 export class PromptConflictError extends Schema.TaggedErrorClass<PromptConflictError>()("Session.PromptConflictError", {
   sessionID: SessionSchema.ID,
@@ -1033,8 +1029,7 @@ const SHELL_MAX_CAPTURE_BYTES = 1024 * 1024
 export const node = makeGlobalNode({
   service: Service,
   layer: layer.pipe(Layer.orDie),
-  // Defer the execution node across the Session/runner module cycle until the graph is compiled.
-  deps: () => [
+  deps: [
     Job.node,
     Database.node,
     EventV2.node,

packages/core/src/session/error.ts

@@ -1,9 +1,15 @@
+export * as SessionErrors from "./error"
+
 import { Schema } from "effect"
 import { Agent } from "@opencode-ai/schema/agent"
 import { SessionMessage } from "./message"
 import { SessionSchema } from "./schema"
 import { SessionError } from "@opencode-ai/schema/session-error"
 
+export class NotFoundError extends Schema.TaggedErrorClass<NotFoundError>()("Session.NotFoundError", {
+  sessionID: SessionSchema.ID,
+}) {}
+
 export class MessageDecodeError extends Schema.TaggedErrorClass<MessageDecodeError>()("Session.MessageDecodeError", {
   sessionID: SessionSchema.ID,
   messageID: SessionMessage.ID,

packages/core/src/session/message-updater.ts

@@ -297,6 +297,12 @@ export function update(adapter: Adapter, event: SessionEvent.Event) {
             draft.cost = event.data.cost
             draft.tokens = castDraft(event.data.tokens)
           }
+          if (event.data.snapshot || event.data.files)
+            draft.snapshot = {
+              ...draft.snapshot,
+              end: event.data.snapshot,
+              files: event.data.files ? Array.from(event.data.files) : undefined,
+            }
         })
       },
       "session.text.started": (event) => {

packages/core/src/session/runner/llm.ts

@@ -143,6 +143,10 @@ const layer = Layer.effect(
               }
             }
             yield* publish(event)
+            if (LLMEvent.is.toolInputError(event)) {
+              if (prepared.resolveToolCall(event.name).type === "settle") needsContinuation = true
+              return
+            }
             if (event.type !== "tool-call" || event.providerExecuted) return
             const tool = prepared.resolveToolCall(event.name)
             if (tool.type === "reject") {
@@ -195,25 +199,27 @@ const layer = Layer.effect(
         tokens: settlement.tokens,
       })
 
-      // Captures the end snapshot, diffs it against the step's start, and durably ends the
-      // assistant step.
+      const captureStepEnd = Effect.fnUntraced(function* () {
+        const snapshot = yield* snapshots.capture()
+        const files =
+          startSnapshot && snapshot
+            ? yield* snapshots
+                .files({ from: startSnapshot, to: snapshot })
+                .pipe(Effect.catch(() => Effect.succeed(undefined)))
+            : undefined
+        return { snapshot, files }
+      })
+
       const publishStepEnd = (settlement: NonNullable<ReturnType<typeof publisher.stepSettlement>>) =>
         Effect.gen(function* () {
-          const endSnapshot = yield* snapshots.capture()
-          const files =
-            startSnapshot && endSnapshot
-              ? yield* snapshots
-                  .files({ from: startSnapshot, to: endSnapshot })
-                  .pipe(Effect.catch(() => Effect.succeed(undefined)))
-              : undefined
+          const end = yield* captureStepEnd()
           yield* serialized(
             events.publish(SessionEvent.Step.Ended, {
               sessionID: session.id,
               assistantMessageID: yield* publisher.startAssistant(),
               finish: settlement.finish,
               ...stepUsage(settlement),
-              snapshot: endSnapshot,
-              files,
+              ...end,
             }),
           )
         })
@@ -253,7 +259,7 @@ const layer = Layer.effect(
                 step: currentStep,
               })
             }
-            yield* serialized(publisher.failAssistant(error))
+            yield* serialized(publisher.failAssistant(error, true))
           }
           // Provider error events only arrive from the stream, so the flag is final here.
           const providerFailed = publisher.hasProviderError()
@@ -274,7 +280,7 @@ const layer = Layer.effect(
           if (settled._tag === "Failure") yield* FiberSet.clear(toolFibers)
           if (userDeclined || streamInterrupted || toolsInterrupted) {
             yield* serialized(publisher.failUnsettledTools({ type: "aborted", message: "Tool execution interrupted" }))
-            yield* serialized(publisher.failAssistant({ type: "aborted", message: "Step interrupted" }))
+            yield* serialized(publisher.failAssistant({ type: "aborted", message: "Step interrupted" }, true))
           }
           // A settled tool fiber failure is one of two things. A defect from a tool
           // implementation becomes a failed tool call the model can read, and the step still
@@ -287,7 +293,7 @@ const layer = Layer.effect(
             const failure = infraError ?? Cause.squash(settledFailure)
             const error = toSessionError(failure)
             yield* serialized(publisher.failUnsettledTools(error))
-            if (infraError !== undefined) yield* serialized(publisher.failAssistant(error))
+            if (infraError !== undefined) yield* serialized(publisher.failAssistant(error, true))
           }
 
           // Fail unresolved calls before the terminal step event. Local calls have joined, so
@@ -315,17 +321,27 @@ const layer = Layer.effect(
               : false
           if (hostedResultMissing && !publisher.stepSettlement())
             yield* serialized(
-              publisher.failAssistant({
-                type: "tool.result-missing",
-                message: "Provider did not return a tool result",
-              }),
+              publisher.failAssistant(
+                {
+                  type: "tool.result-missing",
+                  message: "Provider did not return a tool result",
+                },
+                true,
+              ),
             )
 
           const stepFailure = publisher.stepFailure()
           const stepSettlement = publisher.stepSettlement()
           if (stepSettlement && !stepFailure) yield* publishStepEnd(stepSettlement)
-          if (stepFailure)
-            yield* serialized(publisher.publishStepFailure(stepSettlement ? stepUsage(stepSettlement) : undefined))
+          if (stepFailure) {
+            const end = yield* captureStepEnd()
+            yield* serialized(
+              publisher.publishStepFailure({
+                ...(stepSettlement ? stepUsage(stepSettlement) : {}),
+                ...end,
+              }),
+            )
+          }
 
           if (stream._tag === "Failure") return yield* Effect.failCause(stream.cause)
           if (userDeclined) return yield* Effect.interrupt
@@ -378,7 +394,11 @@ const layer = Layer.effect(
               .pipe(Effect.andThen(Effect.fail(error.cause)))
           }),
         )
-        if (attempt._tag === "Completed") return { needsContinuation: attempt.needsContinuation, step: attempt.step }
+        if (attempt._tag === "Completed")
+          return {
+            needsContinuation: attempt.needsContinuation,
+            step: attempt.step,
+          }
         if (attempt._tag === "RestartAfterOverflowCompaction") recoverOverflow = undefined
         yield* Effect.yieldNow
         currentPromotion = undefined
@@ -410,7 +430,9 @@ const layer = Layer.effect(
               yield* events.publish(SessionEvent.Compaction.Failed, {
                 sessionID,
                 reason: "manual",
-                error: { type: "compaction.failed", message: Cause.pretty(compacted.cause) },
+                error: Cause.hasInterruptsOnly(compacted.cause)
+                  ? { type: "aborted", message: "Compaction cancelled" }
+                  : { type: "compaction.failed", message: Cause.pretty(compacted.cause) },
                 inputID: unsettled.id,
               })
             return yield* Effect.failCause(compacted.cause)

packages/core/src/session/runner/publish-llm-event.ts

@@ -9,6 +9,7 @@ import { SessionError } from "@opencode-ai/schema/session-error"
 import { Money } from "@opencode-ai/schema/money"
 import { AgentV2 } from "../../agent"
 import { Snapshot } from "../../snapshot"
+import { RelativePath } from "../../schema"
 import { SessionUsage } from "../usage"
 
 type Input = {
@@ -112,12 +113,12 @@ export const createLLMEventPublisher = (events: Pick<EventV2.Interface, "publish
         if (state !== undefined) current.state = { ...current.state, ...state }
         return Effect.succeed(current.ordinal)
       })
-    const end = Effect.fnUntraced(function* (id: string, state?: Record<string, unknown>) {
+    const end = Effect.fnUntraced(function* (id: string, state?: Record<string, unknown>, value?: string) {
       const current = chunks.get(id)
       if (!current) return yield* Effect.die(new Error(`${name} end before start: ${id}`))
       yield* ended(
         id,
-        current.values.join(""),
+        value ?? current.values.join(""),
         current.ordinal,
         state === undefined ? current.state : { ...current.state, ...state },
       )
@@ -175,7 +176,11 @@ export const createLLMEventPublisher = (events: Pick<EventV2.Interface, "publish
     yield* toolInput.flush()
   })
 
-  const startToolInput = Effect.fnUntraced(function* (event: { readonly id: string; readonly name: string }) {
+  const startToolInput = Effect.fnUntraced(function* (event: {
+    readonly id: string
+    readonly name: string
+    readonly providerExecuted?: boolean
+  }) {
     if (tools.has(event.id)) return yield* Effect.die(new Error(`Duplicate tool input start: ${event.id}`))
     const assistantMessageID = yield* startAssistant()
     tools.set(event.id, {
@@ -183,7 +188,7 @@ export const createLLMEventPublisher = (events: Pick<EventV2.Interface, "publish
       name: event.name,
       called: false,
       settled: false,
-      providerExecuted: false,
+      providerExecuted: event.providerExecuted === true,
     })
     yield* toolInput.start(event.id)
     yield* events.publish(SessionEvent.Tool.Input.Started, {
@@ -194,13 +199,41 @@ export const createLLMEventPublisher = (events: Pick<EventV2.Interface, "publish
     })
   })
 
-  const endToolInput = Effect.fnUntraced(function* (event: { readonly id: string; readonly name: string }) {
+  const endToolInput = Effect.fnUntraced(function* (
+    event: { readonly id: string; readonly name: string },
+    value?: string,
+  ) {
     const tool = tools.get(event.id)
     if (!tool) return yield* Effect.die(new Error(`Tool input end before start: ${event.id}`))
     if (tool.name !== event.name)
       return yield* Effect.die(new Error(`Tool input name changed for ${event.id}: ${tool.name} -> ${event.name}`))
     if (!toolInput.has(event.id)) return yield* Effect.die(new Error(`Duplicate tool input end: ${event.id}`))
-    yield* toolInput.end(event.id)
+    yield* toolInput.end(event.id, undefined, value)
+  })
+
+  const failMalformedToolInput = Effect.fnUntraced(function* (event: {
+    readonly id: string
+    readonly name: string
+    readonly raw: string
+  }) {
+    if (!tools.has(event.id)) yield* startToolInput(event)
+    const tool = tools.get(event.id)
+    if (!tool || tool.called || tool.settled)
+      return yield* Effect.die(new Error(`Malformed tool input after call settlement: ${event.id}`))
+    if (tool.name !== event.name)
+      return yield* Effect.die(new Error(`Tool input name changed for ${event.id}: ${tool.name} -> ${event.name}`))
+    if (toolInput.has(event.id)) yield* endToolInput(event, event.raw)
+    tool.settled = true
+    yield* events.publish(SessionEvent.Tool.Failed, {
+      sessionID: input.sessionID,
+      assistantMessageID: tool.assistantMessageID,
+      callID: event.id,
+      error: {
+        type: "tool.input-json",
+        message: "Tool call arguments were malformed JSON and were not executed. Retry with valid JSON.",
+      },
+      executed: false,
+    })
   })
 
   const flush = Effect.fn("SessionRunner.flush")(function* () {
@@ -236,9 +269,11 @@ export const createLLMEventPublisher = (events: Pick<EventV2.Interface, "publish
     if (replace || stepFailure === undefined) stepFailure = error
   })
 
-  const publishStepFailure = Effect.fnUntraced(function* (usage?: {
-    readonly cost: Money.USD
-    readonly tokens: ReturnType<typeof SessionUsage.tokens>
+  const publishStepFailure = Effect.fnUntraced(function* (details?: {
+    readonly cost?: Money.USD
+    readonly tokens?: ReturnType<typeof SessionUsage.tokens>
+    readonly snapshot?: Snapshot.ID
+    readonly files?: readonly RelativePath[]
   }) {
     if (stepFailed || stepFailure === undefined) return
     const assistantMessageID = yield* startAssistant()
@@ -247,7 +282,7 @@ export const createLLMEventPublisher = (events: Pick<EventV2.Interface, "publish
       sessionID: input.sessionID,
       assistantMessageID,
       error: stepFailure,
-      ...usage,
+      ...details,
     })
   })
 
@@ -337,6 +372,10 @@ export const createLLMEventPublisher = (events: Pick<EventV2.Interface, "publish
       case "tool-input-end":
         yield* endToolInput(event)
         return
+      case "tool-input-error":
+        retryEvidence = true
+        yield* failMalformedToolInput(event)
+        return
       case "tool-call": {
         retryEvidence = true
         if (!tools.has(event.id)) yield* startToolInput(event)

packages/core/src/session/runner/to-llm-message.ts

@@ -136,14 +136,20 @@ const assistant = (message: SessionMessage.Assistant, model: ModelV2.Ref, provid
         : item.text.length > 0
           ? [{ type: "text", text: item.text }]
           : []
+    const reuseToolProviderMetadata =
+      sameModel &&
+      (message.error === undefined ||
+        (item.executed === true &&
+          (item.state.status === "completed" ||
+            (item.state.status === "error" && item.state.result !== undefined))))
     const call = toolCall(
       item,
-      reuseProviderMetadata ? providerMetadata(providerMetadataKey, item.providerState) : undefined,
+      reuseToolProviderMetadata ? providerMetadata(providerMetadataKey, item.providerState) : undefined,
     )
     if (item.executed !== true) return [call]
     const result = toolResult(
       item,
-      reuseProviderMetadata
+      reuseToolProviderMetadata
         ? providerMetadata(providerMetadataKey, item.providerResultState ?? item.providerState)
         : undefined,
     )

packages/core/src/tool/mcp.ts

@@ -16,8 +16,7 @@ import { ToolRegistry } from "./registry"
  * Registry namespace and permission action names for MCP tools.
  */
 export const namespace = (server: string) => server.replace(/[^a-zA-Z0-9_-]/g, "_")
-export const name = (server: string, tool: string) =>
-  `${namespace(server)}_${tool.replace(/[^a-zA-Z0-9_-]/g, "_")}`
+export const name = (server: string, tool: string) => `${namespace(server)}_${tool.replace(/[^a-zA-Z0-9_-]/g, "_")}`
 
 export const layer = Layer.effectDiscard(
   Effect.gen(function* () {
@@ -33,11 +32,11 @@ export const layer = Layer.effectDiscard(
     // registry never has a gap where MCP tools disappear mid-swap.
     const reconcile = lock.withPermit(
       Effect.gen(function* () {
-        const groups = new Map<string, Record<string, Tool.AnyTool>>()
+        const groups = new Map<string, { tools: Record<string, Tool.AnyTool>; codemode: boolean }>()
         for (const tool of yield* mcp.tools()) {
-          const group = groups.get(tool.server) ?? {}
+          const group = groups.get(tool.server) ?? { tools: {}, codemode: tool.codemode !== false }
           const schema = (tool.inputSchema ?? {}) as JsonSchema.JsonSchema
-          group[tool.name] = Tool.withPermission(
+          group.tools[tool.name] = Tool.withPermission(
             Tool.make({
               description: tool.description ?? "",
               jsonSchema: {
@@ -108,7 +107,7 @@ export const layer = Layer.effectDiscard(
         const next = yield* Scope.fork(scope)
         yield* Effect.forEach(
           groups,
-          ([server, record]) => tools.register(record, { namespace: namespace(server) }),
+          ([server, group]) => tools.register(group.tools, { namespace: namespace(server), codemode: group.codemode }),
           {
             discard: true,
           },

packages/core/test/aisdk.test.ts

@@ -1,11 +1,11 @@
-import type { LanguageModelV3CallOptions } from "@ai-sdk/provider"
+import type { LanguageModelV3, LanguageModelV3CallOptions, LanguageModelV3StreamPart } from "@ai-sdk/provider"
 import { AISDK } from "@opencode-ai/core/aisdk"
 import { ModelV2 } from "@opencode-ai/core/model"
 import { ProviderV2 } from "@opencode-ai/core/provider"
-import { LLM, Message } from "@opencode-ai/ai"
-import { LLMClient } from "@opencode-ai/ai/route"
+import { LLM, LLMError, LLMEvent, Message } from "@opencode-ai/ai"
+import { LLMClient, RequestExecutor } from "@opencode-ai/ai/route"
 import { expect } from "bun:test"
-import { Effect } from "effect"
+import { Effect, Layer } from "effect"
 import { testEffect } from "./lib/effect"
 
 const it = testEffect(AISDK.locationLayer)
@@ -19,6 +19,37 @@ const model = (packageName: string, settings: Record<string, unknown> = {}) =>
     limit: { context: 100, output: 20 },
   })
 
+const streamModel = (events: ReadonlyArray<LanguageModelV3StreamPart>): LanguageModelV3 => ({
+  specificationVersion: "v3",
+  provider: "test",
+  modelId: "test",
+  supportedUrls: {},
+  doGenerate: () => Promise.reject(new Error("Unexpected non-streaming request")),
+  doStream: () =>
+    Promise.resolve({
+      stream: new ReadableStream({
+        start(controller) {
+          events.forEach((event) => controller.enqueue(event))
+          controller.close()
+        },
+      }),
+    }),
+})
+
+const usage = {
+  inputTokens: { total: 1, noCache: 1, cacheRead: 0, cacheWrite: 0 },
+  outputTokens: { total: 1, text: 0, reasoning: 0 },
+} as const
+
+const client = LLMClient.layer.pipe(
+  Layer.provide(
+    Layer.succeed(
+      RequestExecutor.Service,
+      RequestExecutor.Service.of({ execute: () => Effect.die("Unexpected HTTP request") }),
+    ),
+  ),
+)
+
 it.effect("keys language models by package and flattened overlays", () =>
   Effect.gen(function* () {
     const aisdk = yield* AISDK.Service
@@ -238,3 +269,69 @@ it.effect("projects replay metadata onto AI SDK prompt parts", () =>
     ])
   }),
 )
+
+it.effect("emits malformed AI SDK tool input without executing it", () =>
+  Effect.gen(function* () {
+    const aisdk = yield* AISDK.Service
+    const raw = '{"query":"partial'
+    yield* aisdk.hook.sdk((event) => {
+      event.sdk = {
+        languageModel: () =>
+          streamModel([
+            { type: "tool-input-start", id: "call_1", toolName: "lookup" },
+            { type: "tool-input-delta", id: "call_1", delta: raw },
+            { type: "tool-input-end", id: "call_1" },
+            { type: "tool-call", toolCallId: "call_1", toolName: "lookup", input: raw },
+            { type: "finish", finishReason: { unified: "tool-calls", raw: "tool_calls" }, usage },
+          ]),
+      }
+    })
+
+    const resolved = yield* aisdk.model(model("test-ai-sdk"))
+    const response = yield* LLMClient.generate(LLM.request({ model: resolved, prompt: "Lookup" })).pipe(
+      Effect.provide(client),
+    )
+
+    expect(response.events.find(LLMEvent.is.toolInputError)).toMatchObject({
+      id: "call_1",
+      name: "lookup",
+      raw,
+      message: "Invalid JSON input for aisdk tool call lookup",
+    })
+    expect(response.events.some(LLMEvent.is.toolInputEnd)).toBeTrue()
+    expect(response.events.some(LLMEvent.is.toolCall)).toBeFalse()
+  }),
+)
+
+it.effect("keeps malformed provider-executed AI SDK input terminal", () =>
+  Effect.gen(function* () {
+    const aisdk = yield* AISDK.Service
+    const raw = '{"query":"partial'
+    yield* aisdk.hook.sdk((event) => {
+      event.sdk = {
+        languageModel: () =>
+          streamModel([
+            { type: "tool-input-start", id: "call_1", toolName: "web_search", providerExecuted: true },
+            { type: "tool-input-delta", id: "call_1", delta: raw },
+            { type: "tool-input-end", id: "call_1" },
+            {
+              type: "tool-call",
+              toolCallId: "call_1",
+              toolName: "web_search",
+              input: raw,
+              providerExecuted: true,
+            },
+          ]),
+      }
+    })
+
+    const resolved = yield* aisdk.model(model("hosted-test-ai-sdk"))
+    const error = yield* LLMClient.generate(LLM.request({ model: resolved, prompt: "Search" })).pipe(
+      Effect.provide(client),
+      Effect.flip,
+    )
+
+    expect(error).toBeInstanceOf(LLMError)
+    expect(error.message).toContain("Invalid JSON input for aisdk tool call web_search")
+  }),
+)

packages/core/test/config/config.test.ts

@@ -655,6 +655,7 @@ describe("Config", () => {
                       command: ["node", "./mcp/server.js"],
                       environment: { API_KEY: "secret" },
                       disabled: false,
+                      codemode: false,
                       timeout: { catalog: 10000 },
                     },
                     remote: {
@@ -663,6 +664,7 @@ describe("Config", () => {
                       headers: { Authorization: "Bearer token" },
                       oauth: { client_id: "client", scope: "read write", callback_port: 19876 },
                       disabled: true,
+                      codemode: false,
                       timeout: { startup: 15000 },
                     },
                   },
@@ -740,6 +742,7 @@ describe("Config", () => {
                   command: ["node", "./mcp/server.js"],
                   environment: { API_KEY: "secret" },
                   disabled: false,
+                  codemode: false,
                   timeout: { catalog: 10000 },
                 },
                 remote: {
@@ -748,6 +751,7 @@ describe("Config", () => {
                   headers: { Authorization: "Bearer token" },
                   oauth: { client_id: "client", scope: "read write", callback_port: 19876 },
                   disabled: true,
+                  codemode: false,
                   timeout: { startup: 15000 },
                 },
               },

packages/core/test/effect/layer-node/layer-node-types.test.ts

@@ -32,7 +32,6 @@ const b = make({ service: B, layer: bLayer, deps: [a] })
 const c = make({ service: C, layer: cLayer, deps: [a, b] })
 const failing = make({ service: A, layer: failingA, deps: [] })
 const dependent = make({ service: B, layer: bLayer, deps: [failing] })
-make({ service: B, layer: bLayer, deps: () => [a] })
 const inputA = LayerNode.unbound(A, tags.values.app)
 const inputDependent = make({ service: B, layer: bLayer, deps: [inputA] })
 
@@ -47,9 +46,6 @@ make({ service: A, name: "a", layer: aLayer, deps: [] })
 // @ts-expect-error B requires A
 make({ service: B, layer: bLayer, deps: [] })
 
-// @ts-expect-error Lazy dependencies must still provide A
-make({ service: B, layer: bLayer, deps: () => [] })
-
 // @ts-expect-error C requires A and B
 make({ service: C, layer: cLayer, deps: [a] })
 

packages/core/test/effect/layer-node/layer-node.test.ts

@@ -37,12 +37,6 @@ describe("layer node", () => {
     expect(await Effect.runPromise(program)).toBe("hello production")
   })
 
-  test("resolves lazy dependencies when compiling", async () => {
-    const greeting = make({ service: Greeting, layer: greetingLayer, deps: () => [value] })
-    const program = Effect.map(Greeting, (item) => item.value).pipe(Effect.provide(build(greeting)))
-    expect(await Effect.runPromise(program)).toBe("hello production")
-  })
-
   test("exposes roots but hides transitive dependencies", () => {
     const layer = build(LayerNode.group([greeting]))
     const check: Layer.Layer<Greeting> = layer

packages/core/test/fixture/mcp.ts

@@ -9,6 +9,10 @@ export const emptyMcpLayer = Layer.succeed(
   MCP.Service,
   MCP.Service.of({
     servers: () => Effect.succeed([]),
+    add: () => Effect.die("unused mcp.add"),
+    connect: () => Effect.die("unused mcp.connect"),
+    disconnect: () => Effect.die("unused mcp.disconnect"),
+    remove: () => Effect.die("unused mcp.remove"),
     tools: () => Effect.succeed([]),
     callTool: () => Effect.die("unused mcp.callTool"),
     instructions: () => Effect.succeed([]),

packages/core/test/location-mutation.test.ts

@@ -60,11 +60,19 @@ describe("LocationMutation", () => {
     ),
   )
 
-  it.live("rejects a relative lexical escape instead of promoting it to external authority", () =>
+  it.live("requires external-directory authorization for a relative lexical escape", () =>
     withTmp((directory) =>
       Effect.gen(function* () {
-        const error = yield* Effect.flip((yield* LocationMutation.Service).resolve({ path: "../outside.txt" }))
-        expect(error).toMatchObject({ _tag: "LocationMutation.PathError", reason: "relative_escape" })
+        const target = yield* (yield* LocationMutation.Service).resolve({ path: "../outside.txt" })
+        const root = yield* Effect.promise(() => fs.realpath(path.dirname(directory)))
+        expect(target).toMatchObject({
+          canonical: path.join(root, "outside.txt"),
+          resource: path.join(root, "outside.txt").replaceAll("\\", "/"),
+        })
+        expect(target.externalDirectory).toMatchObject({
+          directory: root,
+          resource: path.join(root, "*").replaceAll("\\", "/"),
+        })
       }).pipe(provide(directory)),
     ),
   )

packages/core/test/mcp.test.ts

@@ -148,7 +148,10 @@ function resourceServer(
   )
 }
 
-function resourceMcpLayer(url: string, onFormCreated?: (form: Form.Info) => Effect.Effect<void>) {
+function resourceMcpLayer(
+  server: string | typeof ConfigMCP.Server.Type,
+  onFormCreated?: (form: Form.Info) => Effect.Effect<void>,
+) {
   const directory = AbsolutePath.make(import.meta.dir)
   const unusedIntegration = () => Effect.die("unused integration service")
   return MCP.layer.pipe(
@@ -164,7 +167,12 @@ function resourceMcpLayer(url: string, onFormCreated?: (form: Form.Info) => Effe
                   type: "document",
                   info: new Config.Info({
                     mcp: new ConfigMCP.Info({
-                      servers: { resources: new ConfigMCP.Remote({ type: "remote", url, oauth: false }) },
+                      servers: {
+                        resources:
+                          typeof server === "string"
+                            ? new ConfigMCP.Remote({ type: "remote", url: server, oauth: false })
+                            : server,
+                      },
                     }),
                   }),
                 }),
@@ -224,6 +232,13 @@ const mcp = Layer.mock(MCP.Service, {
           required: ["ok"],
         },
       }),
+      new MCP.Tool({
+        server: MCP.ServerName.make("direct"),
+        name: "lookup",
+        codemode: false,
+        description: "Lookup",
+        inputSchema: { type: "object", properties: {} },
+      }),
     ]),
   callTool: (input) =>
     Effect.sync(() => {
@@ -634,6 +649,120 @@ test("loads and reads MCP resources", async () => {
   )
 })
 
+test("adds, disconnects, and reconnects MCP servers at runtime", async () => {
+  await Effect.runPromise(
+    Effect.scoped(
+      Effect.gen(function* () {
+        yield* Effect.gen(function* () {
+          const service = yield* MCP.Service
+
+          expect((yield* service.servers())[0]?.status).toEqual({ status: "disabled" })
+          expect(yield* service.connect("missing").pipe(Effect.flip)).toBeInstanceOf(MCP.NotFoundError)
+          expect(yield* service.disconnect("missing").pipe(Effect.flip)).toBeInstanceOf(MCP.NotFoundError)
+          yield* service.add(
+            "dynamic",
+            new ConfigMCP.Local({
+              type: "local",
+              command: [process.execPath, path.join(import.meta.dir, "fixture/mcp-output-schema.ts")],
+            }),
+          )
+          expect((yield* service.servers()).find((server) => server.name === "dynamic")?.status).toEqual({
+            status: "connected",
+          })
+
+          yield* service.add(
+            "dynamic",
+            new ConfigMCP.Local({
+              type: "local",
+              command: [process.execPath, path.join(import.meta.dir, "fixture/mcp-output-schema.ts")],
+              disabled: true,
+            }),
+          )
+          expect((yield* service.servers()).find((server) => server.name === "dynamic")?.status).toEqual({
+            status: "disabled",
+          })
+          expect(yield* service.tools()).toEqual([])
+
+          yield* service.connect("dynamic")
+          expect((yield* service.servers()).find((server) => server.name === "dynamic")?.status).toEqual({
+            status: "connected",
+          })
+          yield* service.disconnect("dynamic")
+          expect((yield* service.servers()).find((server) => server.name === "dynamic")?.status).toEqual({
+            status: "disabled",
+          })
+          expect(yield* service.tools()).toEqual([])
+
+          yield* service.connect("dynamic")
+          expect((yield* service.servers()).find((server) => server.name === "dynamic")?.status).toEqual({
+            status: "connected",
+          })
+
+          yield* service.remove("dynamic")
+          expect((yield* service.servers()).some((server) => server.name === "dynamic")).toBe(false)
+          expect(yield* service.tools()).toEqual([])
+          expect(yield* service.remove("dynamic").pipe(Effect.flip)).toBeInstanceOf(MCP.NotFoundError)
+        }).pipe(
+          Effect.provide(
+            resourceMcpLayer(
+              new ConfigMCP.Local({
+                type: "local",
+                command: [process.execPath, path.join(import.meta.dir, "fixture/mcp-output-schema.ts")],
+                disabled: true,
+              }),
+            ),
+          ),
+        )
+      }),
+    ),
+  )
+})
+
+test("serializes concurrent MCP lifecycle operations", async () => {
+  await Effect.runPromise(
+    Effect.scoped(
+      Effect.gen(function* () {
+        yield* Effect.gen(function* () {
+          const service = yield* MCP.Service
+
+          // Whatever order the racing operations land in, the resulting state must be consistent.
+          yield* Effect.all(
+            [
+              service.connect("resources"),
+              service.connect("resources"),
+              service.disconnect("resources"),
+              service.connect("resources"),
+            ],
+            { concurrency: "unbounded", discard: true },
+          )
+          const status = (yield* service.servers()).find((server) => server.name === "resources")?.status
+          const tools = yield* service.tools()
+          expect(status?.status === "connected" || status?.status === "disabled").toBe(true)
+          if (status?.status === "disabled") expect(tools).toEqual([])
+          if (status?.status === "connected") expect(tools.length).toBeGreaterThan(0)
+
+          yield* service.disconnect("resources")
+          expect((yield* service.servers())[0]?.status).toEqual({ status: "disabled" })
+          expect(yield* service.tools()).toEqual([])
+          yield* service.connect("resources")
+          expect((yield* service.servers())[0]?.status).toEqual({ status: "connected" })
+          expect((yield* service.tools()).length).toBeGreaterThan(0)
+        }).pipe(
+          Effect.provide(
+            resourceMcpLayer(
+              new ConfigMCP.Local({
+                type: "local",
+                command: [process.execPath, path.join(import.meta.dir, "fixture/mcp-output-schema.ts")],
+                disabled: true,
+              }),
+            ),
+          ),
+        )
+      }),
+    ),
+  )
+})
+
 it.effect("advertises MCP output schemas to Code Mode", () =>
   Effect.gen(function* () {
     const registry = yield* ToolRegistry.Service
@@ -644,6 +773,18 @@ it.effect("advertises MCP output schemas to Code Mode", () =>
   }),
 )
 
+it.effect("advertises MCP tools directly when Code Mode is disabled for the server", () =>
+  Effect.gen(function* () {
+    const registry = yield* ToolRegistry.Service
+    yield* waitForTool(registry, "direct_lookup")
+    const definitions = yield* toolDefinitions(registry)
+    const execute = definitions.find((tool) => tool.name === "execute")
+
+    expect(definitions.some((tool) => tool.name === "direct_lookup")).toBe(true)
+    expect(execute?.description).not.toContain("tools.direct.lookup")
+  }),
+)
+
 it.effect("waits for permission before calling an MCP tool", () =>
   Effect.gen(function* () {
     calls = 0

packages/core/test/session-runner-message.test.ts

@@ -565,6 +565,22 @@ Recent work
               text: "Partial thought",
               state: { itemId: "rs_failed", reasoningEncryptedContent: null },
             }),
+            SessionMessage.AssistantTool.make({
+              type: "tool",
+              id: "hosted-completed",
+              name: "web_search",
+              executed: true,
+              providerState: { itemId: "call_completed" },
+              providerResultState: { itemId: "result_completed" },
+              state: SessionMessage.ToolStateCompleted.make({
+                status: "completed",
+                input: { query: "Effect" },
+                content: [],
+                structured: {},
+                result: { type: "json", value: { found: true } },
+              }),
+              time: { created, completed: created },
+            }),
             SessionMessage.AssistantTool.make({
               type: "tool",
               id: "hosted-failed",
@@ -592,6 +608,22 @@ Recent work
 
     expect(messages[0]?.content).toEqual([
       { type: "text", text: "Partial thought" },
+      {
+        type: "tool-call",
+        id: "hosted-completed",
+        name: "web_search",
+        input: { query: "Effect" },
+        providerExecuted: true,
+        providerMetadata: { provider: { itemId: "call_completed" } },
+      },
+      {
+        type: "tool-result",
+        id: "hosted-completed",
+        name: "web_search",
+        result: { type: "json", value: { found: true } },
+        providerExecuted: true,
+        providerMetadata: { provider: { itemId: "result_completed" } },
+      },
       {
         type: "tool-call",
         id: "hosted-failed",

packages/core/test/session-runner-tool-events.test.ts

@@ -9,6 +9,8 @@ import { SessionMessage } from "@opencode-ai/core/session/message"
 import { SessionV2 } from "@opencode-ai/core/session"
 import { ModelV2 } from "@opencode-ai/core/model"
 import { ProviderV2 } from "@opencode-ai/core/provider"
+import { RelativePath } from "@opencode-ai/core/schema"
+import { Snapshot } from "@opencode-ai/core/snapshot"
 import { createLLMEventPublisher } from "@opencode-ai/core/session/runner/publish-llm-event"
 
 const sessionID = SessionV2.ID.make("ses_tool_event_test")
@@ -229,6 +231,8 @@ test("content-filter finish retains failure evidence until step closeout", async
     publisher.publishStepFailure({
       cost: Money.USD.make(1.25),
       tokens: settlement.tokens,
+      snapshot: Snapshot.ID.make("tree-end"),
+      files: [RelativePath.make("src/changed.ts")],
     }),
   )
   expect(published.map((event) => event.type)).toEqual(["session.step.started.1", "session.step.failed.1"])
@@ -236,6 +240,8 @@ test("content-filter finish retains failure evidence until step closeout", async
     error: { type: "provider.content-filter", message: "Provider blocked the response" },
     cost: 1.25,
     tokens: { input: 8, output: 2, reasoning: 1 },
+    snapshot: "tree-end",
+    files: ["src/changed.ts"],
   })
 })
 

packages/core/test/session-runner.test.ts

@@ -1892,6 +1892,35 @@ describe("SessionRunnerLLM", () => {
     }),
   )
 
+  it.effect("records cancelled manual compaction without surfacing an internal failure", () =>
+    Effect.gen(function* () {
+      const session = yield* setup
+      response = reply.text("Earlier answer", "text-manual-interrupt-history")
+      yield* admit(session, "Earlier question")
+      yield* session.resume(sessionID)
+
+      const streamed = yield* Deferred.make<void>()
+      const partial = fragmentFixture("text", "text-manual-interrupt-summary", ["Partial summary"])
+      responseStream = Stream.concat(
+        Stream.fromIterable(partial.partialEvents),
+        Stream.fromEffect(Deferred.succeed(streamed, undefined)).pipe(Stream.flatMap(() => Stream.never)),
+      )
+      const compaction = yield* session.compact({ sessionID })
+      const run = yield* session.resume(sessionID).pipe(Effect.forkChild)
+      yield* Deferred.await(streamed)
+      yield* session.interrupt(sessionID)
+
+      yield* Fiber.await(run)
+      expect(yield* SessionPending.compaction((yield* Database.Service).db, sessionID)).toBeUndefined()
+      expect((yield* session.messages({ sessionID })).find((message) => message.id === compaction.id)).toMatchObject({
+        type: "compaction",
+        status: "failed",
+        reason: "manual",
+        error: { type: "aborted", message: "Compaction cancelled" },
+      })
+    }),
+  )
+
   it.effect("settles an admitted manual compaction when pre-start resolution throws", () =>
     Effect.gen(function* () {
       const session = yield* setup
@@ -4135,6 +4164,326 @@ describe("SessionRunnerLLM", () => {
     }),
   )
 
+  it.effect("continues after malformed local tool input without exposing raw arguments", () =>
+    Effect.gen(function* () {
+      const session = yield* setup
+      yield* admit(session, "Recover malformed tool input")
+      const marker = "raw-malformed-marker"
+      const raw = `{"text":"${marker}`
+      responses = [
+        [
+          LLMEvent.stepStart({ index: 0 }),
+          LLMEvent.toolInputStart({ id: "call-malformed", name: "echo" }),
+          LLMEvent.toolInputDelta({ id: "call-malformed", name: "echo", text: raw }),
+          LLMEvent.toolInputEnd({ id: "call-malformed", name: "echo" }),
+          LLMEvent.toolInputError({
+            id: "call-malformed",
+            name: "echo",
+            raw,
+            message: "Invalid JSON input for test tool call echo",
+          }),
+          LLMEvent.stepFinish({ index: 0, reason: "tool-calls" }),
+          LLMEvent.finish({ reason: "tool-calls" }),
+        ],
+        reply.stop(),
+      ]
+
+      yield* session.resume(sessionID)
+
+      expect(requests).toHaveLength(2)
+      expect(executions).toEqual([])
+      expect(JSON.stringify(requests[1])).not.toContain(marker)
+      expect(requests[1]?.messages).toEqual(
+        expect.arrayContaining([
+          expect.objectContaining({
+            role: "assistant",
+            content: expect.arrayContaining([
+              expect.objectContaining({ type: "tool-call", id: "call-malformed", name: "echo", input: {} }),
+            ]),
+          }),
+          expect.objectContaining({
+            role: "tool",
+            content: expect.arrayContaining([
+              expect.objectContaining({
+                type: "tool-result",
+                id: "call-malformed",
+                result: expect.objectContaining({
+                  type: "error",
+                  value: expect.objectContaining({
+                    error: expect.objectContaining({
+                      message: "Tool call arguments were malformed JSON and were not executed. Retry with valid JSON.",
+                    }),
+                  }),
+                }),
+              }),
+            ]),
+          }),
+        ]),
+      )
+      const context = yield* session.context(sessionID)
+      const failed = context.find(
+        (message): message is SessionMessage.Assistant =>
+          message.type === "assistant" && message.content.some((item) => item.type === "tool"),
+      )
+      expect(failed).toMatchObject({
+        content: [
+          {
+            type: "tool",
+            id: "call-malformed",
+            executed: false,
+            state: {
+              status: "error",
+              input: {},
+              error: {
+                type: "tool.input-json",
+                message: "Tool call arguments were malformed JSON and were not executed. Retry with valid JSON.",
+              },
+            },
+          },
+        ],
+      })
+      if (!failed) throw new Error("Malformed tool assistant missing")
+      expect(failed.error).toBeUndefined()
+      expect((yield* recordedStepSettlementEvents(sessionID, failed.id)).map((event) => event.type)).toEqual([
+        "session.step.started.1",
+        "session.tool.failed.1",
+        "session.step.ended.1",
+      ])
+      const database = (yield* Database.Service).db
+      const durable = yield* database
+        .select({ type: EventTable.type, data: EventTable.data })
+        .from(EventTable)
+        .where(eq(EventTable.aggregate_id, sessionID))
+        .all()
+        .pipe(Effect.orDie)
+      expect(durable.find((event) => event.type === "session.tool.input.ended.1")?.data).toMatchObject({
+        callID: "call-malformed",
+        text: raw,
+      })
+    }),
+  )
+
+  it.effect("settles a valid sibling before recovering malformed tool input", () =>
+    Effect.gen(function* () {
+      const session = yield* setup
+      yield* admit(session, "Run parallel tools")
+      toolExecutionGate = yield* Deferred.make<void>()
+      toolExecutionsStarted = yield* Deferred.make<void>()
+      toolExecutionsReady = 1
+      responses = [
+        [
+          LLMEvent.stepStart({ index: 0 }),
+          LLMEvent.toolCall({ id: "call-valid", name: "echo", input: { text: "valid" } }),
+          LLMEvent.toolInputError({
+            id: "call-malformed",
+            name: "echo",
+            raw: '{"text":"partial',
+            message: "Invalid JSON input for test tool call echo",
+          }),
+          LLMEvent.stepFinish({ index: 0, reason: "tool-calls" }),
+          LLMEvent.finish({ reason: "tool-calls" }),
+        ],
+        reply.stop(),
+      ]
+
+      const run = yield* session.resume(sessionID).pipe(Effect.forkChild)
+      yield* Deferred.await(toolExecutionsStarted)
+      expect(requests).toHaveLength(1)
+      yield* Deferred.succeed(toolExecutionGate, undefined)
+      yield* Fiber.join(run)
+      toolExecutionGate = undefined
+      toolExecutionsStarted = undefined
+
+      expect(requests).toHaveLength(2)
+      expect(executions).toEqual(["valid"])
+      const request = requests[1]
+      if (!request) throw new Error("Malformed recovery request missing")
+      expect(request.messages.flatMap((message) => (message.role === "tool" ? message.content : []))).toEqual(
+        expect.arrayContaining([
+          expect.objectContaining({ id: "call-valid", type: "tool-result" }),
+          expect.objectContaining({ id: "call-malformed", type: "tool-result" }),
+        ]),
+      )
+    }),
+  )
+
+  it.effect("does not recover malformed input after sibling execution is interrupted", () =>
+    Effect.gen(function* () {
+      const session = yield* setup
+      yield* admit(session, "Interrupt malformed recovery")
+      toolExecutionGate = yield* Deferred.make<void>()
+      toolExecutionsStarted = yield* Deferred.make<void>()
+      toolExecutionsReady = 1
+      response = [
+        LLMEvent.stepStart({ index: 0 }),
+        LLMEvent.toolCall({ id: "call-valid", name: "echo", input: { text: "blocked" } }),
+        LLMEvent.toolInputError({
+          id: "call-malformed",
+          name: "echo",
+          raw: '{"text":"partial',
+          message: "Invalid JSON input for test tool call echo",
+        }),
+        LLMEvent.stepFinish({ index: 0, reason: "tool-calls" }),
+        LLMEvent.finish({ reason: "tool-calls" }),
+      ]
+
+      const run = yield* session.resume(sessionID).pipe(Effect.forkChild)
+      yield* Deferred.await(toolExecutionsStarted)
+      while (
+        !(yield* session.context(sessionID)).some(
+          (message) =>
+            message.type === "assistant" &&
+            message.content.some((item) => item.type === "tool" && item.id === "call-malformed"),
+        )
+      )
+        yield* Effect.yieldNow
+      yield* session.interrupt(sessionID)
+      toolExecutionGate = undefined
+      toolExecutionsStarted = undefined
+
+      expect(yield* Fiber.await(run)).toMatchObject({ _tag: "Failure" })
+      expect(requests).toHaveLength(1)
+      expect(yield* session.context(sessionID)).toMatchObject([
+        { type: "user", text: "Interrupt malformed recovery" },
+        {
+          type: "assistant",
+          error: { type: "aborted", message: "Step interrupted" },
+          content: [
+            { type: "tool", id: "call-valid", state: { status: "error", error: { type: "aborted" } } },
+            { type: "tool", id: "call-malformed", state: { status: "error" } },
+          ],
+        },
+      ])
+    }),
+  )
+
+  it.effect("records malformed provider-executed input as executed", () =>
+    Effect.gen(function* () {
+      const session = yield* setup
+      yield* admit(session, "Fail malformed hosted input")
+      const failure = new LLMError({
+        module: "test",
+        method: "stream",
+        reason: new InvalidProviderOutputReason({ message: "Invalid hosted tool input" }),
+      })
+      responseStream = Stream.fromIterable([
+        LLMEvent.stepStart({ index: 0 }),
+        LLMEvent.toolInputStart({ id: "call-hosted", name: "web_search", providerExecuted: true }),
+        LLMEvent.toolInputDelta({ id: "call-hosted", name: "web_search", text: '{"query":"partial' }),
+      ]).pipe(Stream.concat(Stream.fail(failure)))
+
+      expect(yield* session.resume(sessionID).pipe(Effect.flip)).toBe(failure)
+      expect(requireAssistant(yield* session.context(sessionID))).toMatchObject({
+        error: { type: "provider.invalid-output", message: "Invalid hosted tool input" },
+        content: [
+          {
+            type: "tool",
+            id: "call-hosted",
+            executed: true,
+            state: { status: "error", error: { type: "provider.invalid-output" } },
+          },
+        ],
+      })
+    }),
+  )
+
+  it.effect("replaces malformed input diagnosis with a later provider failure", () =>
+    Effect.gen(function* () {
+      const session = yield* setup
+      yield* admit(session, "Fail after malformed input")
+      const failure = new LLMError({
+        module: "test",
+        method: "stream",
+        reason: new InvalidProviderOutputReason({ message: "Provider failed after malformed input" }),
+      })
+      responseStream = Stream.fromIterable([
+        LLMEvent.stepStart({ index: 0 }),
+        LLMEvent.toolInputError({
+          id: "call-malformed",
+          name: "echo",
+          raw: '{"text":"partial',
+          message: "Invalid JSON input for test tool call echo",
+        }),
+      ]).pipe(Stream.concat(Stream.fail(failure)))
+
+      expect(yield* session.resume(sessionID).pipe(Effect.flip)).toBe(failure)
+      expect(requireAssistant(yield* session.context(sessionID))).toMatchObject({
+        error: { type: "provider.invalid-output", message: "Provider failed after malformed input" },
+        content: [
+          {
+            type: "tool",
+            id: "call-malformed",
+            executed: false,
+            state: { status: "error", error: { type: "tool.input-json" } },
+          },
+        ],
+      })
+      expect(requests).toHaveLength(1)
+    }),
+  )
+
+  it.effect("continues after repeated malformed tool input", () =>
+    Effect.gen(function* () {
+      const session = yield* setup
+      yield* admit(session, "Keep producing malformed tools")
+      const malformed = (id: string) => [
+        LLMEvent.stepStart({ index: 0 }),
+        LLMEvent.toolInputError({
+          id,
+          name: "echo",
+          raw: '{"text":"partial',
+          message: "Invalid JSON input for test tool call echo",
+        }),
+        LLMEvent.stepFinish({ index: 0, reason: "tool-calls" }),
+        LLMEvent.finish({ reason: "tool-calls" }),
+      ]
+      responses = [
+        malformed("call-first"),
+        reply.tool("call-valid-between", "echo", { text: "valid" }),
+        malformed("call-second"),
+        reply.stop(),
+      ]
+
+      yield* session.resume(sessionID)
+
+      expect(requests).toHaveLength(4)
+      expect(executions).toEqual(["valid"])
+      expect((yield* recordedEventTypes(sessionID)).filter((type) => type === "session.step.failed.1")).toHaveLength(0)
+    }),
+  )
+
+  it.effect("does not continue malformed tool input past the agent step limit", () =>
+    Effect.gen(function* () {
+      const session = yield* setup
+      const agents = yield* AgentV2.Service
+      yield* agents.transform((editor) =>
+        editor.update(AgentV2.ID.make("build"), (agent) => {
+          agent.steps = 2
+        }),
+      )
+      yield* admit(session, "Stop malformed tools at the step limit")
+      const malformed = (id: string) => [
+        LLMEvent.stepStart({ index: 0 }),
+        LLMEvent.toolInputError({
+          id,
+          name: "echo",
+          raw: '{"text":"partial',
+          message: "Invalid JSON input for test tool call echo",
+        }),
+        LLMEvent.stepFinish({ index: 0, reason: "tool-calls" }),
+        LLMEvent.finish({ reason: "tool-calls" }),
+      ]
+      responses = [malformed("call-first"), malformed("call-at-limit")]
+
+      yield* session.resume(sessionID)
+
+      expect(requests).toHaveLength(2)
+      expect(requests[0]?.toolChoice).toBeUndefined()
+      expect(requests[1]?.toolChoice).toMatchObject({ type: "none" })
+      expect((yield* recordedEventTypes(sessionID)).filter((type) => type === "session.tool.failed.1")).toHaveLength(2)
+    }),
+  )
+
   it.effect("does not continue automatically after a provider error follows a local tool call", () =>
     Effect.gen(function* () {
       const session = yield* setup

packages/core/test/tool-patch.test.ts

@@ -277,6 +277,38 @@ describe("PatchTool", () => {
     ),
   )
 
+  it.live("approves a relative external target before reading update content", () =>
+    Effect.acquireUseRelease(
+      Effect.promise(() => Promise.all([tmpdir(), tmpdir()])),
+      ([active, outside]) => {
+        reset()
+        const target = path.join(outside.path, "external.txt")
+        const relative = path.relative(active.path, target)
+        return Effect.promise(() => fs.writeFile(target, "before\n")).pipe(
+          Effect.andThen(
+            withTool(active.path, (registry) =>
+              Effect.gen(function* () {
+                expect(
+                  yield* executeTool(
+                    registry,
+                    call(`*** Begin Patch\n*** Update File: ${relative}\n@@\n-before\n+after\n*** End Patch`),
+                  ),
+                ).toMatchObject({ type: "text" })
+                expect(assertions.map((input) => input.action)).toEqual(["external_directory", "edit"])
+                expect(readsBeforeEditApproval).toBe(0)
+                expect(yield* Effect.promise(() => fs.readFile(target, "utf8"))).toBe("after\n")
+              }),
+            ),
+          ),
+        )
+      },
+      ([active, outside]) =>
+        Effect.promise(() =>
+          Promise.all([active[Symbol.asyncDispose](), outside[Symbol.asyncDispose]()]).then(() => undefined),
+        ),
+    ),
+  )
+
   it.live("approves one external directory scope for multiple files under the same parent", () =>
     Effect.acquireUseRelease(
       Effect.promise(() => Promise.all([tmpdir(), tmpdir()])),

packages/core/test/tool-shell.test.ts

@@ -2,7 +2,7 @@ import fs from "fs/promises"
 import { realpathSync } from "node:fs"
 import path from "path"
 import { describe, expect, test } from "bun:test"
-import { DateTime, Duration, Effect, Fiber, Layer, Scope, Stream } from "effect"
+import { DateTime, Deferred, Duration, Effect, Fiber, Layer, Scope, Stream } from "effect"
 import { Money } from "@opencode-ai/schema/money"
 import { AppNodeBuilder } from "@opencode-ai/core/effect/app-node-builder"
 import { LayerNode } from "@opencode-ai/core/effect/layer-node"
@@ -166,10 +166,10 @@ const overflowCommand = (bytes: number) =>
   isWindows
     ? `[Console]::Out.Write(('x' * ${bytes})); Start-Sleep -Milliseconds 100`
     : `head -c ${bytes} /dev/zero | tr '\\0' 'x'`
-const progressOverflowCommand = (bytes: number) =>
+const progressOverflowCommand = (bytes: number, release: string) =>
   isWindows
-    ? `[Console]::Out.Write(('x' * ${bytes})); Start-Sleep -Milliseconds 1500`
-    : `head -c ${bytes} /dev/zero | tr '\\0' 'x'; sleep 1.5`
+    ? `[Console]::Out.Write(('x' * ${bytes})); while (!(Test-Path -LiteralPath '${release}')) { Start-Sleep -Milliseconds 50 }`
+    : `head -c ${bytes} /dev/zero | tr '\\0' 'x'; while [ ! -e '${release}' ]; do sleep 0.05; done`
 
 const withSession = <A, E, R>(directory: string, body: (registry: ToolRegistry.Interface) => Effect.Effect<A, E, R>) =>
   Effect.gen(function* () {
@@ -417,33 +417,49 @@ describe("ShellTool", () => {
     ),
   )
 
-  it.live("reports bounded output progress for a running command", () =>
-    Effect.acquireUseRelease(
-      Effect.promise(() => tmpdir()),
-      (tmp) => {
-        reset()
-        const bytes = ShellTool.MAX_CAPTURE_BYTES + 1024
-        return withSession(tmp.path, (registry) =>
-          Effect.gen(function* () {
-            const progress: ToolRegistry.Progress[] = []
-            yield* settleTool(registry, {
-              ...call({ command: progressOverflowCommand(bytes) }, "call-progress"),
-              progress: (update) => Effect.sync(() => progress.push(update)),
-            })
+  it.live(
+    "reports bounded output progress for a running command",
+    () =>
+      Effect.acquireUseRelease(
+        Effect.promise(() => tmpdir()),
+        (tmp) => {
+          reset()
+          const release = "shell-progress-release"
+          const releasePath = path.join(tmp.path, release)
+          return withSession(tmp.path, (registry) =>
+            Effect.gen(function* () {
+              const observed = yield* Deferred.make<ToolRegistry.Progress>()
+              yield* settleTool(registry, {
+                ...call(
+                  { command: progressOverflowCommand(ShellTool.MAX_CAPTURE_BYTES + 1024, release) },
+                  "call-progress",
+                ),
+                progress: (update) =>
+                  Effect.gen(function* () {
+                    if (update.structured.truncated !== true) return
+                    const content = update.content[0]
+                    if (content?.type !== "text") return
+                    if (content.text.indexOf("\n\n[output truncated; full output saved to:") !== ShellTool.MAX_CAPTURE_BYTES)
+                      return
+                    yield* Deferred.succeed(observed, update)
+                    yield* Effect.promise(() => fs.writeFile(releasePath, ""))
+                  }),
+              })
 
-            expect(progress).toHaveLength(1)
-            expect(progress[0]?.structured).toEqual({ truncated: true })
-            const content = progress[0]?.content[0]
-            expect(content?.type).toBe("text")
-            if (content?.type !== "text") return
-            expect(content.text.indexOf("\n\n[output truncated; full output saved to:")).toBe(
-              ShellTool.MAX_CAPTURE_BYTES,
-            )
-          }),
-        )
-      },
-      (tmp) => Effect.promise(() => tmp[Symbol.asyncDispose]().then(() => undefined)),
-    ),
+              const progress = yield* Deferred.await(observed)
+              expect(progress.structured).toEqual({ truncated: true })
+              const content = progress.content[0]
+              expect(content?.type).toBe("text")
+              if (content?.type !== "text") return
+              expect(content.text.indexOf("\n\n[output truncated; full output saved to:")).toBe(
+                ShellTool.MAX_CAPTURE_BYTES,
+              )
+            }).pipe(Effect.ensuring(Effect.promise(() => fs.writeFile(releasePath, "")).pipe(Effect.ignore))),
+          )
+        },
+        (tmp) => Effect.promise(() => tmp[Symbol.asyncDispose]().then(() => undefined)),
+      ),
+    { timeout: 15_000 },
   )
 
   it.live("returns a useful timeout settlement", () =>

packages/docs/mcp-servers.mdx

@@ -75,6 +75,7 @@ A local server is a command that OpenCode starts using the MCP stdio transport.
 | `cwd` | No | Process working directory. Relative paths resolve from the workspace directory; the workspace is the default. |
 | `environment` | No | String environment variables added to the inherited OpenCode process environment. |
 | `disabled` | No | Set to `true` to prevent the server from connecting. Defaults to `false`. |
+| `codemode` | No | Set to `false` to expose the server's tools directly to the model instead of through Code Mode. Defaults to `true`. |
 | `timeout` | No | Per-server timeout overrides. |
 
 Use `{env:NAME}` to substitute an environment variable while loading config. Shell expressions such as `$NAME` are not expanded in JSON strings.
@@ -108,6 +109,7 @@ A remote server uses the MCP Streamable HTTP transport. Its `url` must be a vali
 | `headers` | No | String HTTP headers sent to the MCP endpoint. |
 | `oauth` | No | OAuth client settings, or `false` to disable OAuth support. |
 | `disabled` | No | Set to `true` to prevent the server from connecting. Defaults to `false`. |
+| `codemode` | No | Set to `false` to expose the server's tools directly to the model instead of through Code Mode. Defaults to `true`. |
 | `timeout` | No | Per-server timeout overrides. |
 
 Use `oauth: false` for a server that exclusively uses an API key or another header-based credential.
@@ -223,6 +225,22 @@ OpenCode combines the server name and MCP tool name as `<server>_<tool>`. Charac
 
 Choose short server names that remain unique after normalization. Under the default Code Mode, MCP tools are grouped by the normalized server name.
 
+Set `codemode` to `false` on a server when its tools should remain on the provider's native tool list:
+
+```jsonc
+{
+  "mcp": {
+    "servers": {
+      "context7": {
+        "type": "remote",
+        "url": "https://mcp.context7.com/mcp",
+        "codemode": false
+      }
+    }
+  }
+}
+```
+
 Use permission actions to hide or deny a server's tools without stopping its connection:
 
 ```jsonc

packages/schema/src/session-event.ts

@@ -276,6 +276,8 @@ export namespace Step {
       error: SessionError.Error,
       cost: Money.USD.pipe(optional),
       tokens: TokenUsage.Info.pipe(optional),
+      snapshot: Snapshot.ID.pipe(optional),
+      files: Schema.Array(RelativePath).pipe(optional),
     },
   })
   export type Failed = typeof Failed.Type

packages/simulation/package.json

@@ -18,6 +18,9 @@
   },
   "dependencies": {
     "@fontsource/commit-mono": "5.2.5",
+    "@fontsource/noto-sans-math": "5.2.5",
+    "@fontsource/noto-sans-symbols": "5.2.5",
+    "@fontsource/noto-sans-symbols-2": "5.2.5",
     "@napi-rs/canvas": "1.0.2",
     "@opencode-ai/core": "workspace:*",
     "@opencode-ai/ai": "workspace:*",

packages/simulation/src/frontend/png.ts

@@ -5,16 +5,29 @@ import regularFont from "@fontsource/commit-mono/files/commit-mono-latin-400-nor
 import boldFont from "@fontsource/commit-mono/files/commit-mono-latin-700-normal.woff2" with { type: "file" }
 import italicFont from "@fontsource/commit-mono/files/commit-mono-latin-400-italic.woff2" with { type: "file" }
 import boldItalicFont from "@fontsource/commit-mono/files/commit-mono-latin-700-italic.woff2" with { type: "file" }
+import symbolFont from "@fontsource/noto-sans-symbols/files/noto-sans-symbols-symbols-400-normal.woff2" with { type: "file" }
+import symbolFont2 from "@fontsource/noto-sans-symbols-2/files/noto-sans-symbols-2-symbols-400-normal.woff2" with { type: "file" }
+import brailleFont from "@fontsource/noto-sans-symbols-2/files/noto-sans-symbols-2-braille-400-normal.woff2" with { type: "file" }
+import mathFont from "@fontsource/noto-sans-math/files/noto-sans-math-math-400-normal.woff2" with { type: "file" }
 
 const CellWidth = 10
 const CellHeight = 20
 const FontSize = 16
 const FontFamily = "OpenCode Mono"
+const SymbolFontFamily = "OpenCode Symbols"
+const SymbolFontFamily2 = "OpenCode Symbols 2"
+const MathFontFamily = "OpenCode Math"
+const FontStack = `"${FontFamily}", "${SymbolFontFamily}", "${SymbolFontFamily2}", "${MathFontFamily}"`
 
-for (const file of [regularFont, boldFont, italicFont, boldItalicFont]) {
+for (const [file, family] of [
+  ...[regularFont, boldFont, italicFont, boldItalicFont].map((file) => [file, FontFamily] as const),
+  [symbolFont, SymbolFontFamily],
+  [symbolFont2, SymbolFontFamily2],
+  [brailleFont, SymbolFontFamily2],
+  [mathFont, MathFontFamily],
+] as const) {
   const font = Buffer.from(await Bun.file(file).arrayBuffer())
-  if (!GlobalFonts.register(font, FontFamily))
-    throw new Error(`Failed to register screenshot font: ${file}`)
+  if (!GlobalFonts.register(font, family)) throw new Error(`Failed to register screenshot font: ${file}`)
 }
 
 export function screenshot(renderer: CliRenderer) {
@@ -55,7 +68,7 @@ export function screenshotFrame(frame: CapturedFrame) {
           const x = column * CellWidth
           const y = row * CellHeight
           if (!drawBlockElement(context, char, x, y, cells)) {
-            context.font = `${attributes & TextAttributes.ITALIC ? "italic " : ""}${attributes & TextAttributes.BOLD ? "bold " : ""}${FontSize}px "${FontFamily}"`
+            context.font = `${attributes & TextAttributes.ITALIC ? "italic " : ""}${attributes & TextAttributes.BOLD ? "bold " : ""}${FontSize}px ${FontStack}`
             context.fillText(char, x, y + 1)
           }
           if (attributes & TextAttributes.UNDERLINE) {

packages/simulation/test/png.test.ts

@@ -29,6 +29,38 @@ test("renders captured frames with bundled fonts", () => {
   expect(image.data.subarray(1, 4).toString()).toBe("PNG")
 })
 
+test("renders OpenCode symbols instead of missing-glyph boxes", async () => {
+  const pixels = async (text: string) => {
+    const image = SimulationPng.screenshotFrame({
+      cols: 1,
+      rows: 1,
+      cursor: [0, 0],
+      lines: [
+        {
+          spans: [
+            {
+              text,
+              width: 1,
+              fg: RGBA.fromInts(255, 255, 255),
+              bg: RGBA.fromInts(0, 0, 0),
+              attributes: 0,
+            },
+          ],
+        },
+      ],
+    })
+    const canvas = createCanvas(image.width, image.height)
+    const context = canvas.getContext("2d")
+    context.drawImage(await loadImage(image.data), 0, 0)
+    return [...context.getImageData(0, 0, image.width, image.height).data]
+  }
+
+  const missingGlyph = await pixels("\u{10ffff}")
+  for (const symbol of ["△", "✱", "⇆", "⠹"]) {
+    expect(await pixels(symbol)).not.toEqual(missingGlyph)
+  }
+})
+
 test("fills adjacent block elements without glyph gaps", async () => {
   const image = SimulationPng.screenshotFrame({
     cols: 2,
@@ -97,7 +129,5 @@ test("draws heavy vertical box elements on cell boundaries", async () => {
   expect([...context.getImageData(4, 0, 2, 30).data]).toEqual(
     Array.from({ length: 60 }, () => [255, 255, 255, 255]).flat(),
   )
-  expect([...context.getImageData(4, 30, 2, 10).data]).toEqual(
-    Array.from({ length: 20 }, () => [0, 0, 0, 255]).flat(),
-  )
+  expect([...context.getImageData(4, 30, 2, 10).data]).toEqual(Array.from({ length: 20 }, () => [0, 0, 0, 255]).flat())
 })

packages/tui/src/config/v1/keybind.ts

@@ -123,8 +123,8 @@ export const Definitions = {
   mcp_list: keybind("none", "List MCP servers"),
   provider_connect: keybind("none", "Connect integration"),
   agent_list: keybind("<leader>a", "List agents"),
-  agent_cycle: keybind("tab", "Next agent"),
-  agent_cycle_reverse: keybind("shift+tab", "Previous agent"),
+  agent_cycle: keybind("shift+tab", "Next agent"),
+  agent_cycle_reverse: keybind("none", "Previous agent"),
   variant_cycle: keybind("ctrl+t", "Cycle model variants"),
   variant_list: keybind("none", "List model variants"),
 

packages/tui/src/routes/session/composer/index.tsx

@@ -22,6 +22,7 @@ interface Tab {
 const ComposerContext = createContext<{
   register: (tab: Tab) => () => void
   active: (id: string) => boolean
+  close: () => void
 }>()
 
 export function useComposerTab() {
@@ -73,6 +74,7 @@ export function Composer(props: ComposerProps) {
     active(id: string) {
       return props.open && store.active === id
     },
+    close,
   }
 
   const keymap = Keymap.use()

packages/tui/src/routes/session/composer/shell-tab.tsx

@@ -59,9 +59,11 @@ export function ShellTab(props: { sessionID: string }) {
         group: "Composer",
         bind: "up",
         run() {
-          const list = entries()
-          if (list.length === 0) return
-          setStore("selected", (prev) => (prev - 1 + list.length) % list.length)
+          if (store.selected === 0) {
+            composer.close()
+            return
+          }
+          setStore("selected", (prev) => prev - 1)
         },
       },
       {

packages/tui/src/routes/session/composer/subagents-tab.tsx

@@ -160,9 +160,11 @@ export function SubagentsTab(props: { sessionID: string }) {
         group: "Composer",
         bind: "up",
         run() {
-          const list = entries()
-          if (list.length === 0) return
-          moveTo((store.selected - 1 + list.length) % list.length, true)
+          if (store.selected === 0) {
+            composer.close()
+            return
+          }
+          moveTo(store.selected - 1, true)
         },
       },
       {

packages/tui/src/routes/session/index.tsx

@@ -111,6 +111,7 @@ export function Session() {
   const route = useRouteData("session")
   const { navigate } = useRoute()
   const data = useData()
+  const local = useLocal()
   const paths = useTuiPaths()
   const configState = useConfig()
   const config = configState.data
@@ -184,6 +185,24 @@ export function Session() {
   const scrollAcceleration = createMemo(() => getScrollAcceleration(config))
   const toast = useToast()
   const client = useClient()
+  const autoApproved = new Set<string>()
+  createEffect(() => {
+    if (local.permission.mode !== "auto") return
+    permissions().forEach((request) => {
+      if (autoApproved.has(request.id)) return
+      autoApproved.add(request.id)
+      void client.api.permission
+        .reply({
+          sessionID: request.sessionID,
+          reply: "once",
+          requestID: request.id,
+        })
+        .catch((error) => {
+          autoApproved.delete(request.id)
+          toast.error(error)
+        })
+    })
+  })
   const editor = useEditorContext()
   const rows = createSessionRows(() => route.sessionID)
   const boundaries = createMemo(() => messageBoundaryIDs(rows, messages()))
@@ -1440,9 +1459,10 @@ function CompactionMessage(props: { message: Extract<SessionMessageInfo, { type:
   const ctx = use()
   const { themeV2, syntax } = useTheme()
   const status = () => props.message.status
-  const text = () => (props.message.status === "failed" ? props.message.error.message : props.message.summary)
+  const cancelled = () => props.message.status === "failed" && props.message.error.type === "aborted"
+  const text = () => (props.message.status === "failed" ? (cancelled() ? "" : props.message.error.message) : props.message.summary)
   const content = createMemo(() => text().trim())
-  const color = () => (status() === "failed" ? themeV2.text.feedback.error() : themeV2.text.subdued())
+  const color = () => (status() === "failed" && !cancelled() ? themeV2.text.feedback.error() : themeV2.text.subdued())
   return (
     <box>
       <box flexDirection="row" alignItems="center">
@@ -1454,11 +1474,14 @@ function CompactionMessage(props: { message: Extract<SessionMessageInfo, { type:
                 <spinner frames={SPINNER_FRAMES} interval={80} color={color()} />
               </Show>
             </Match>
-            <Match when={status() === "failed"}>
+            <Match when={status() === "failed" && !cancelled()}>
               <text fg={color()}>✗</text>
             </Match>
           </Switch>
           <text fg={color()}>Compaction</text>
+          <Show when={cancelled()}>
+            <text fg={color()}>· cancelled</text>
+          </Show>
         </box>
         <box border={["top"]} borderColor={color()} flexGrow={1} />
       </box>

packages/tui/test/keybind.test.ts

@@ -0,0 +1,7 @@
+import { expect, test } from "bun:test"
+import { TuiKeybind } from "../src/config/keybind"
+
+test("binds agent cycling only to shift+tab by default", () => {
+  expect(TuiKeybind.Definitions.agent_cycle.default).toBe("shift+tab")
+  expect(TuiKeybind.Definitions.agent_cycle_reverse.default).toBe("none")
+})

specs/v2/schema-changelog.md

@@ -385,8 +385,8 @@ Affected schema:
 
 Change:
 
-- Resolve relative mutation paths within the active Location.
-- Accept absolute internal paths and require explicit `external_directory` approval before leaf approval for external absolute paths.
+- Resolve relative mutation paths from the active Location.
+- Require explicit `external_directory` approval before leaf approval for external paths.
 - Keep named references read-oriented and reject them for mutation.
 - Revalidate path authority immediately before write mechanics.