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Filename Latest commit message Latest commit date
camillelawrence 1d0473ba75
 feat: SEP-2260 stream-based enforcement of client receive-side request association (#1055) 
* refactor(service): express SEP-2260 receive-side association as an enum

Replaces the has_pending_outbound_request bool on
enforce_peer_request_association with PeerRequestAssociation, so a
stream-separating transport can report per-request association (#1033).
Behavior-preserving: the event loop still passes the coarse signal as
Unknown.

* feat(transport): record inbound stream origin on streamable HTTP client (#1033)

The worker attaches an InboundStreamOrigin extension to each inbound
server request: Unassociated for the standalone GET stream,
OutboundRequest(id) for a POST's SSE stream. Mirror of the
OriginatingRequestId marker used by the server side.

* feat(service): enforce SEP-2260 client receive-side check per stream origin (#1033)

The event loop maps InboundStreamOrigin plus the in-flight responder
pool to PeerRequestAssociation: restricted requests arriving on the
standalone GET stream are now rejected with -32602 even while unrelated
outbound requests are in flight.

* test: end-to-end SEP-2260 stream-based enforcement over streamable HTTP (#1033)

* docs: cross-link SEP-2260 stream markers

* test: origin marker survives SSE resumption per SEP-2260 (#1033)

A POST SSE stream resumed via GET + Last-Event-ID (SEP-1699) reconnects
beneath execute_sse_stream, so requests replayed after a resume keep
their OutboundRequest origin. Pins the layering invariant: hoisting
reconnection above the marker attach point would wrongly reject
associated requests with -32602.

* docs: trim SEP-2260 comments to spec rationale

* docs: align SEP-2577 expect reason with sibling suppressions

* test: harden SEP-2260 stream-enforcement e2e (#1033)

Detect handler invocation via a channel asserted empty instead of a
panic in a spawned task (swallowed, cannot fail the test); surface
scripted-server misuse as transport errors rather than panics in the
transport task; bound the tail awaits with 5s timeouts. Correct the
header comment: a 2026-07-28 server minting a session id is not
spec-legal (SEP-2567 removes sessions and the GET endpoint) — the
scripted server is deliberately non-conforming, which is the point of
receive-side enforcement.

* test: adapt SEP-2260 association tests to ServerPeerInfo

Rebase onto 3.0.0: RoleClient::PeerInfo is now ServerPeerInfo (#1065)
and its constructor takes the protocol version directly.

* chore: add 'Copy' macro to new PeerRequestAssociation

Co-authored-by: Dale Seo <5466341+DaleSeo@users.noreply.github.com>

---------

Co-authored-by: Dale Seo <5466341+DaleSeo@users.noreply.github.com>
2026-07-29 19:59:47 -04:00
..
src feat: SEP-2260 stream-based enforcement of client receive-side request association (#1055) 2026-07-29 19:59:47 -04:00
tests feat: SEP-2260 stream-based enforcement of client receive-side request association (#1055) 2026-07-29 19:59:47 -04:00
build.rs chore: add pre-commit hook for conventional commit verification (#619) 2026-01-14 16:01:28 -05:00
Cargo.toml fix: gate client handler bounds for local (#1068) 2026-07-28 11:02:32 -04:00
CHANGELOG.md chore: release v3.0.1 (#1081) 2026-07-29 16:53:31 -04:00
README.md docs: prepare for stable 3.0 release (#1073) 2026-07-28 15:09:56 -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.