From a626be423816402e09e1c7f8717cb70414a7bdab Mon Sep 17 00:00:00 2001
From: Kit Langton <kit.langton@gmail.com>
Date: Sat, 2 May 2026 14:28:44 -0400
Subject: [PATCH] fix(telemetry): emit Tool.execute span for MCP and plugin
 tools

MCP-served tools and plugin-defined tools were bypassing the Tool.execute
span that wraps native tool runs. Native tools get the span via wrap() in
tool/tool.ts, called from Tool.define(); MCP tools are constructed as AI
SDK dynamicTools in mcp/index.ts and inserted via a parallel path in
session/prompt.ts, and plugin tools are built in registry.ts fromPlugin()
without going through Tool.define().

Verified against trace 33c8941c89094d50650c2b91e244c778: 28 ai.toolCall
spans had only 24 Tool.execute children; the missing 4 were all MCP tools
(sentry_*, exa_*). Cross-cutting telemetry filtering on
operation=Tool.execute was silently dropping MCP and plugin traffic.
---
 packages/opencode/src/session/prompt.ts | 15 ++++++++++++---
 packages/opencode/src/tool/registry.ts  | 11 ++++++++++-
 2 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/packages/opencode/src/session/prompt.ts b/packages/opencode/src/session/prompt.ts
index fb822ff17e8b..80c47d3ceda0 100644
--- a/packages/opencode/src/session/prompt.ts
+++ b/packages/opencode/src/session/prompt.ts
@@ -464,9 +464,18 @@ NOTE: At any point in time through this workflow you should feel free to ask the
                 { tool: key, sessionID: ctx.sessionID, callID: opts.toolCallId },
                 { args },
               )
-              yield* ctx.ask({ permission: key, metadata: {}, patterns: ["*"], always: ["*"] })
-              const result: Awaited<ReturnType<NonNullable<typeof execute>>> = yield* Effect.promise(() =>
-                execute(args, opts),
+              const result: Awaited<ReturnType<NonNullable<typeof execute>>> = yield* Effect.gen(function* () {
+                yield* ctx.ask({ permission: key, metadata: {}, patterns: ["*"], always: ["*"] })
+                return yield* Effect.promise(() => execute(args, opts))
+              }).pipe(
+                Effect.withSpan("Tool.execute", {
+                  attributes: {
+                    "tool.name": key,
+                    "tool.call_id": opts.toolCallId,
+                    "session.id": ctx.sessionID,
+                    "message.id": input.processor.message.id,
+                  },
+                }),
               )
               yield* plugin.trigger(
                 "tool.execute.after",
diff --git a/packages/opencode/src/tool/registry.ts b/packages/opencode/src/tool/registry.ts
index a9a853e504eb..ebe3bb530cde 100644
--- a/packages/opencode/src/tool/registry.ts
+++ b/packages/opencode/src/tool/registry.ts
@@ -154,7 +154,16 @@ export const layer: Layer.Layer<
                     ...(out.truncated && { outputPath: out.outputPath }),
                   },
                 }
-              }),
+              }).pipe(
+                Effect.withSpan("Tool.execute", {
+                  attributes: {
+                    "tool.name": id,
+                    "session.id": toolCtx.sessionID,
+                    "message.id": toolCtx.messageID,
+                    ...(toolCtx.callID ? { "tool.call_id": toolCtx.callID } : {}),
+                  },
+                }),
+              ),
           }
         }