Function serveMcpStdio

serveMcpStdio(bus: McpBus, options?: McpStdioOptions): () => void
Serve the bus as an MCP server over stdio (Node only): newline-delimited JSON-RPC 2.0 on process.stdin in, process.stdout out. This is the transport MCP clients like Claude Desktop spawn subprocess servers with.

Unparseable lines get a JSON-RPC -32700 parse error; everything else is routed through createMcpHandler. Returns a stop() function that detaches from stdin.

Two input-driven limits keep a hostile or broken client from growing memory without bound — see McpStdioOptions.maxLineLength and McpStdioOptions.maxInFlight.

Replies are written in COMPLETION order, not arrival order: messages are dispatched concurrently, so a fast tool answers before a slow one issued earlier. That is deliberate and JSON-RPC-legal — responses may arrive in any order and id correlates them — and it is what keeps one slow tool call from blocking every reply queued behind it.

IMPORTANT: while serving, do not console.log to stdout — it would corrupt the protocol stream. Log to stderr instead.
Parameters
- bus: McpBus
- Optionaloptions: McpStdioOptions
Returns () => void
Example
```
// mcp-server.ts — spawned by an MCP client
const bus = createSchemaCommandBus(schema);
bus.use(agentOrigin(), { priority: 150 });
registerHandlers(bus);
const stop = serveMcpStdio(bus, { actions: ['cart*', 'productGet'] });
process.on('SIGTERM', stop);
```
- Defined in mcp.ts:416