XMCP

Overview

Use this skill to stand up or extend an xmcp server quickly, including adapter wiring, tool discovery, auth middleware, and production build output. The full docs are in references/xmcp-docs.md.

Workflow

1. Identify host framework (Next.js, Express, NestJS, or standalone).
2. Bootstrap with npx init-xmcp@latest and confirm tool/prompt/resource directories.
3. Wire the /mcp endpoint using the adapter output.
4. Add tools, prompts, resources with schemas and metadata.
5. Configure auth or middleware if needed.
6. Run xmcp dev and xmcp build and verify the .xmcp output is generated.
7. Debug path aliases and TypeScript config if the adapter import fails.

Adapter decision guide

• Next.js: use the route handler and export GET/POST from the adapter.
• Express: import the handler from the adapter output and mount GET/POST.
• NestJS: use the generated module/controller and add the module to AppModule.

Tool authoring checklist

• Export a schema and metadata in each tool file.
• Ensure tool filenames are in the tools directory so auto-discovery works.
• Keep schemas minimal and descriptive to help tool selection.

Auth and middleware

• Prefer server-side auth and never expose secrets to the browser.
• For API key or JWT middleware, ensure headers are set by the MCP client.
• For OAuth providers, configure environment variables and middleware exports.

Troubleshooting

• Missing @xmcp/adapter import: run npx xmcp build and add TS path aliases.
• Adapter output missing: confirm xmcp dev or xmcp build ran successfully.
• Requests failing: verify /mcp route registration and middleware ordering.

References

• references/xmcp-docs.md contains the full documentation snapshot.