modelcontextprotocol/rust-sdk
Watch
1
0
Fork
You've already forked rust-sdk
 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions 1
rust-sdk/crates/rmcp
History
Repository files (latest commit first)
Filename Latest commit message Latest commit date
lutz-grex 2f8d3b7355
 Fix/issue 817 idle timeout log level (#824) 
* fix(transport): downgrade idle timeout log from error to debug

Idle keep-alive timeout is normal zombie-session cleanup, not a transport failure.

Route it through a dedicated WorkerQuitReason::IdleTimeout variant.

Log it at debug level instead of treating it as a fatal error.

Remove the unused LocalSessionWorkerError::KeepAliveTimeout variant.

Closes #817

* fix(session): tolerate dead worker in close_session

Swallow SessionServiceTerminated in close_session when the worker has already exited.
This prevents a spurious ERROR log during the post-exit cleanup path in
spawn_session_worker.

* fix(transport): address PR review feedback

- deprecate KeepAliveTimeout
- harden tests
2026-05-04 20:14:06 -04:00
..
src Fix/issue 817 idle timeout log level (#824) 2026-05-04 20:14:06 -04:00
tests Fix/issue 817 idle timeout log level (#824) 2026-05-04 20:14:06 -04:00
build.rs chore: add pre-commit hook for conventional commit verification (#619) 2026-01-14 16:01:28 -05:00
Cargo.toml feat: optional session store (resumabillity support) (#775) 2026-04-21 17:06:18 -04:00
CHANGELOG.md chore: release v1.6.0 (#818) 2026-05-01 09:38:25 -04:00
README.md feat: add local feature for !Send tool handler support (#740) 2026-03-11 17:22:56 -04:00

README.md

rmcp

Crates.io Documentation

The official Rust SDK for the Model Context Protocol. Build MCP servers that expose tools, resources, and prompts to AI assistants — or build clients that connect to them.

For getting started, usage guides, and full MCP feature documentation (resources, prompts, sampling, roots, logging, completions, subscriptions, etc.), see the main README.

Feature Flags

Feature Description Default
server Server functionality and the tool system ✅
client Client functionality
macros #[tool] / #[prompt] macros (re-exports rmcp-macros) ✅
schemars JSON Schema generation for tool definitions
auth OAuth 2.0 authentication support
elicitation Elicitation support

Transport features

Feature Description
transport-io Server-side stdio transport
transport-child-process Client-side stdio transport (spawns a child process)
transport-async-rw Generic async read/write transport
transport-streamable-http-client Streamable HTTP client (transport-agnostic)
transport-streamable-http-client-reqwest Streamable HTTP client with default reqwest backend
transport-streamable-http-server Streamable HTTP server transport

TLS backend options (for HTTP transports)

Feature Description
reqwest Uses rustls — pure Rust TLS (recommended default)
reqwest-native-tls Uses platform-native TLS (OpenSSL / Secure Transport / SChannel)
reqwest-tls-no-provider Uses rustls without a default crypto provider (bring your own)

Transports

The transport layer is pluggable. Two built-in pairs cover the most common cases:

Client Server
stdio TokioChildProcess stdio
Streamable HTTP StreamableHttpClientTransport StreamableHttpService

Any type that implements the Transport trait can be used. The IntoTransport helper trait provides automatic conversions from:

  1. (Sink, Stream) or a combined Sink + Stream
  2. (AsyncRead, AsyncWrite) or a combined AsyncRead + AsyncWrite
  3. A Worker implementation
  4. A Transport implementation directly

License

This project is licensed under the terms specified in the repository's LICENSE file.