feat(opencode): state whether the code mode tool list is complete or partial

The preview now reports its own comprehensiveness so the model knows when it
has the whole catalog vs. when it must search:

- Overall: "This is the COMPLETE list ..." when every tool fits the budget,
  else "This is a PARTIAL list — X of Y tools are shown ...".
- Per namespace: a fully-shown server reads `- github (2 tools)`; a truncated
  one is annotated `- alpha (70 tools, 31 shown)` or `- zeta (1 tool, none shown)`.

When complete, the model isn't pushed toward needless $rune.search calls; when
partial, exactly what's missing is unambiguous.

packages/opencode/src/session/code-mode.ts

@@ -200,26 +200,50 @@ export function describe(groups: Map<string, CatalogEntry[]>): string {
     lines.push("", "No MCP servers are currently connected.")
     return lines.join("\n")
   }
+  // Select which signatures fit the budget (cheapest first within each server,
+  // servers alphabetical) before emitting, so the list can state exactly how
+  // comprehensive it is — overall and per namespace.
+  const ordered = [...groups].sort(([a], [b]) => a.localeCompare(b))
+  const shown = new Map<string, string[]>()
+  let used = 0
+  let budgetLeft = true
+  let totalTools = 0
+  let totalShown = 0
+  for (const [server, entries] of ordered) {
+    totalTools += entries.length
+    const picked: string[] = []
+    if (budgetLeft) {
+      for (const entry of entries) {
+        const line = `  - ${previewSignature(entry)}`
+        if (used + line.length > PREVIEW_BUDGET) {
+          budgetLeft = false
+          break
+        }
+        picked.push(line)
+        used += line.length
+      }
+    }
+    shown.set(server, picked)
+    totalShown += picked.length
+  }
+
+  const complete = totalShown === totalTools
   lines.push(
     "",
-    "Every connected server is listed below with its tool count. A budgeted sample of tool",
-    "signatures is shown inline; any tool not shown must be found with `tools.$rune.search` /",
-    "`tools.$rune.describe` before you call it.",
+    complete
+      ? "This is the COMPLETE list of available tools — every connected tool is shown below with its call signature. Use `tools.$rune.describe(path)` for a tool's full types."
+      : `This is a PARTIAL list — ${totalShown} of ${totalTools} tools are shown below. Any tool not listed must be found with \`tools.$rune.search\` first; use \`tools.$rune.describe(path)\` for full types.`,
   )
-  let used = 0
-  let previewing = true
-  for (const [server, entries] of [...groups].sort(([a], [b]) => a.localeCompare(b))) {
-    lines.push(`- ${server} (${entries.length} tool${entries.length === 1 ? "" : "s"})`)
-    if (!previewing) continue
-    for (const entry of entries) {
-      const line = `  - ${previewSignature(entry)}`
-      if (used + line.length > PREVIEW_BUDGET) {
-        previewing = false
-        break
-      }
-      lines.push(line)
-      used += line.length
-    }
+  for (const [server, entries] of ordered) {
+    const picked = shown.get(server)!
+    const total = entries.length
+    const count = `${total} tool${total === 1 ? "" : "s"}`
+    // Annotate only when a namespace is not fully shown, so a comprehensive
+    // namespace reads cleanly and a truncated one is unambiguous.
+    const label =
+      picked.length === total ? count : picked.length === 0 ? `${count}, none shown` : `${count}, ${picked.length} shown`
+    lines.push(`- ${server} (${label})`)
+    for (const line of picked) lines.push(line)
   }
   return lines.join("\n")
 }