modelcontextprotocol/typescript-sdk
Watch
1
0
Fork
You've already forked typescript-sdk
 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions 1

feat(core): reserved trace context _meta keys and propagation docs (SEP-414) (#2270)

Browse source 
Co-authored-by: Felix Weinberger <3823880+felixweinberger@users.noreply.github.com>
This commit is contained in:
Matt 2026-06-15 13:32:08 +01:00 • committed by GitHub
commit 78fbe2736d
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
1 changed files with 330 additions and 5 deletions
Download patch file Download diff file Expand all files Collapse all files

26
examples/server/src/serverGuide.examples.ts
View file

@ -13,7 +13,7 @@ import { randomUUID } from 'node:crypto';
import { createMcpExpressApp } from '@modelcontextprotocol/express';
import { NodeStreamableHTTPServerTransport } from '@modelcontextprotocol/node';
import type { CallToolResult, ResourceLink } from '@modelcontextprotocol/server';
import { completable, McpServer, ResourceTemplate } from '@modelcontextprotocol/server';
import { completable, McpServer, ResourceTemplate, TRACEPARENT_META_KEY } from '@modelcontextprotocol/server';
import { StdioServerTransport } from '@modelcontextprotocol/server/stdio';
import * as z from 'zod/v4';
//#endregion imports
@ -319,6 +319,29 @@ function registerTool_progress(server: McpServer) {
//#endregion registerTool_progress
}
/** Example: Tool that reads W3C Trace Context from request `_meta`. */
function registerTool_traceContext(server: McpServer) {
//#region registerTool_traceContext
server.registerTool(
'traced-operation',
{
description: 'Operation that participates in distributed tracing',
inputSchema: z.object({ query: z.string() })
},
async ({ query }, ctx): Promise<CallToolResult> => {
// e.g. '00-4bf92f3577b34da6a3ce929d0e0e4736-00f067aa0ba902b7-01'
const traceparent = ctx.mcpReq._meta?.[TRACEPARENT_META_KEY];
if (typeof traceparent === 'string') {
// Continue the caller's trace, e.g. start a child span with your
// OpenTelemetry tracer using this trace context.
}
return { content: [{ type: 'text', text: `Results for ${query}` }] };
}
);
//#endregion registerTool_traceContext
}
// ---------------------------------------------------------------------------
// Server-initiated requests
// ---------------------------------------------------------------------------
@ -543,6 +566,7 @@ void registerTool_errorHandling;
void registerTool_annotations;
void registerTool_logging;
void registerTool_progress;
void registerTool_traceContext;
void registerTool_sampling;
void registerTool_elicitation;
void registerTool_roots;