fix(mcp): apply timeouts to prompts and resources

rekram1-node · Jun 10, 2026 · Jun 10, 2026 · Jun 10, 2026 · Jun 10, 2026 · Jun 10, 2026
commit b5ad6434b43c35d3e8afcb9b697bd79b0422e896
diff --git a/packages/opencode/src/mcp/index.ts b/packages/opencode/src/mcp/index.ts
@@ -740,7 +740,7 @@ export const layer = Layer.effect(
 
     const withClient = Effect.fnUntraced(function* <A>(
       clientName: string,
-      fn: (client: MCPClient) => Promise<A>,
+      fn: (client: MCPClient, timeout?: number) => Promise<A>,
       label: string,
       meta?: Record<string, unknown>,
     ) {
@@ -750,8 +750,11 @@ export const layer = Layer.effect(
         yield* Effect.logWarning(`client not found for ${label}`, { clientName })
         return undefined
       }
+      const cfg = yield* cfgSvc.get()
+      const configured = cfg.mcp?.[clientName]
+      const entry = configured && isMcpConfigured(configured) ? configured : s.config[clientName]
       return yield* Effect.tryPromise({
-        try: () => fn(client),
+        try: () => fn(client, entry?.timeout ?? cfg.experimental?.mcp_timeout),
         catch: (error) => error,
       }).pipe(
         Effect.tapError((error) =>
@@ -770,15 +773,21 @@ export const layer = Layer.effect(
       name: string,
       args?: Record<string, string>,
     ) {
-      return yield* withClient(clientName, (client) => client.getPrompt({ name, arguments: args }), "getPrompt", {
-        promptName: name,
-      })
+      return yield* withClient(
+        clientName,
+        (client, timeout) => client.getPrompt({ name, arguments: args }, { timeout }),
+        "getPrompt",
+        { promptName: name },
+      )
     })
 
     const readResource = Effect.fn("MCP.readResource")(function* (clientName: string, resourceUri: string) {
-      return yield* withClient(clientName, (client) => client.readResource({ uri: resourceUri }), "readResource", {
-        resourceUri,
-      })
+      return yield* withClient(
+        clientName,
+        (client, timeout) => client.readResource({ uri: resourceUri }, { timeout }),
+        "readResource",
+        { resourceUri },
+      )
     })
 
     const getMcpConfig = Effect.fnUntraced(function* (mcpName: string) {

diff --git a/packages/opencode/test/mcp/lifecycle.test.ts b/packages/opencode/test/mcp/lifecycle.test.ts
@@ -13,6 +13,8 @@ interface MockClientState {
   listToolsCalls: number
   listPromptsCalls: number
   listResourcesCalls: number
+  getPromptTimeout?: number
+  readResourceTimeout?: number
   requestCalls: number
   listToolsShouldFail: boolean
   listToolsError: string
@@ -206,6 +208,16 @@ void mock.module("@modelcontextprotocol/sdk/client/index.js", () => ({
       return { resources: this._state?.resources ?? [] }
     }
 
+    async getPrompt(_params: unknown, options?: { timeout?: number }) {
+      if (this._state) this._state.getPromptTimeout = options?.timeout
+      return { messages: [] }
+    }
+
+    async readResource(params: { uri: string }, options?: { timeout?: number }) {
+      if (this._state) this._state.readResourceTimeout = options?.timeout
+      return { contents: [{ uri: params.uri, text: "test" }] }
+    }
+
     async close() {
       if (this._state) this._state.closed = true
     }
@@ -758,6 +770,51 @@ it.instance(
   },
 )
 
+it.instance(
+  "uses per-server timeouts for prompt and resource requests",
+  () =>
+    MCP.Service.use((mcp: MCPNS.Interface) =>
+      Effect.gen(function* () {
+        lastCreatedClientName = "timeout-server"
+        const serverState = getOrCreateClientState("timeout-server")
+
+        yield* mcp.add("timeout-server", {
+          type: "local",
+          command: ["echo", "test"],
+          timeout: 2500,
+        })
+        yield* mcp.getPrompt("timeout-server", "test")
+        yield* mcp.readResource("timeout-server", "test://resource")
+
+        expect(serverState.getPromptTimeout).toBe(2500)
+        expect(serverState.readResourceTimeout).toBe(2500)
+      }),
+    ),
+  { config: { mcp: {}, experimental: { mcp_timeout: 5000 } } },
+)
+
+it.instance(
+  "uses the experimental MCP timeout as the request fallback",
+  () =>
+    MCP.Service.use((mcp: MCPNS.Interface) =>
+      Effect.gen(function* () {
+        lastCreatedClientName = "fallback-server"
+        const serverState = getOrCreateClientState("fallback-server")
+
+        yield* mcp.add("fallback-server", {
+          type: "local",
+          command: ["echo", "test"],
+        })
+        yield* mcp.getPrompt("fallback-server", "test")
+        yield* mcp.readResource("fallback-server", "test://resource")
+
+        expect(serverState.getPromptTimeout).toBe(5000)
+        expect(serverState.readResourceTimeout).toBe(5000)
+      }),
+    ),
+  { config: { mcp: {}, experimental: { mcp_timeout: 5000 } } },
+)
+
 it.instance(
   "resource-only servers connect without listing tools",
   () =>