Messages API MCP connector
The thinnest Anthropic client by design: tool calls only, one bearer token per server, and no local servers. Anthropic documents that you obtain and refresh the token before the API call.
- Client type
- API
- Protocol revision
2025-11-25
Support
Messages API MCP connector
- stdio
- No
- Streamable HTTP
- Yes
- Legacy SSE
- Yes
- Revision
2025-11-25- OAuth flow
- No
- Registration
- No
- Metadata doc
- No
- Client ID
- No
- resource
- No
- iss
- No
- Headers
- No
- Protocol revision
2025-11-25. The connector documentation cites that revision's authorization specification for token semantics.
Caveats and sources
Each one names the column it qualifies and cites the page it comes from, which is often not the page in the row's primary source.
- Runs the OAuth flow
- Documented as the caller's job: API consumers handle the flow, obtain the access token before the call, and refresh it as needed. The only credential field is
authorization_token. Source - Protocol features
- Of the specification's feature set, only tool calls are supported. The documented workaround for resources and prompts is the SDK's client-side MCP helpers, which run your MCP client rather than Anthropic's. Source
Primary source
This row was last verified July 31, 2026 against the 2026-07-28 revision.