
- Web connectors → hosted HTTP MCP servers (accessible via URL).
- Desktop extensions → local processes running on your machine.

-v bind mount:
- Start your MCP server (example:
http://127.0.0.1:3001). - In Claude go to Tools → Add connectors → Add custom connector.
- Enter the MCP HTTP endpoint. Typical endpoints:
- Streamable HTTP:
http://127.0.0.1:3001/mcp - SSE:
http://127.0.0.1:3001/sse
- Streamable HTTP:
- Confirm you trust the connector when prompted.
When adding a custom connector pointing to a local server, verify the MCP service is reachable at the URL you provide (correct host, port, and path). If you run behind a firewall or use a different network interface, update the host accordingly.
- Model Context Protocol (MCP) Inspector (npm): run
npx @modelcontextprotocol/inspectorand openhttp://localhost:5173/to inspect MCP traffic. - Useful for debugging request/response flows, session management, and events.
| Connector Type | Description | Typical Endpoint / Example |
|---|---|---|
| STDIO-backed MCP servers | Local processes invoked by the desktop client | N/A (process-level) |
| Streamable HTTP endpoints | HTTP endpoints supporting Streamable HTTP sessions | http://127.0.0.1:3001/mcp |
| SSE endpoints | Server-Sent Events endpoints used for streaming updates | http://127.0.0.1:3001/sse |
| Goal | Recommendation |
|---|---|
| Keep services up long-term | Run MCP servers as background services (systemd, launchd) |
| Isolate dependencies | Run MCP servers in Docker containers |
| Team/internal access | Host MCP servers on an internal network, or expose public endpoints only after securing them |
Do not expose MCP endpoints publicly unless you understand and have implemented proper authentication, TLS, and access controls. Exposing local connectors without protection can leak sensitive data.
- Is the MCP server running? Check logs for successful startup.
- Is the URL/path correct? Confirm whether the server expects
/mcp(Streamable HTTP) or/sse. - Is the host reachable from the machine running Claude? Replace
127.0.0.1with the machine’s IP if necessary for networked setups. - Use the MCP Inspector to view session traffic and errors.
- Claude: https://claude.ai
- Model Context Protocol Inspector (npm): https://www.npmjs.com/package/@modelcontextprotocol/inspector
- OpenTools (community registries): https://opentools.com
- Docker: https://www.docker.com
- Python venv: https://docs.python.org/3/library/venv.html