fix: require metadata for modern HTTP requests - #1089
Merged
DaleSeo merged 1 commit intoJul 30, 2026
Merged
Conversation
Copy link
Copy Markdown
Member
Sorry, something went wrong.
DaleSeo
marked this pull request as ready for review
July 29, 2026 23:58
9 tasks
alexhancock
approved these changes
Jul 30, 2026
Merged
howardjohn
pushed a commit
to agentgateway/agentgateway
that referenced
this pull request
Jul 31, 2026
Bump to latest stable release https://github.com/modelcontextprotocol/rust-sdk/releases/tag/rmcp-v3.1.0 ``` Added classify authorization-required errors (modelcontextprotocol/rust-sdk#1056) add strict stateless protocol metadata validation (modelcontextprotocol/rust-sdk#1091) SEP-2260 stream-based enforcement of client receive-side request association (modelcontextprotocol/rust-sdk#1055) Fixed (model) decode metadata-bearing input-required results affecting mrtr (modelcontextprotocol/rust-sdk#1097) require metadata for modern HTTP requests (modelcontextprotocol/rust-sdk#1089) honor supported_protocol_versions when negotiating initialize (modelcontextprotocol/rust-sdk#1093) Other document the ping utility with examples (modelcontextprotocol/rust-sdk#1106) complete Tier 1 feature docs and finalize roadmap (modelcontextprotocol/rust-sdk#1101) (conformance) meeting requirements for tier 1 (modelcontextprotocol/rust-sdk#1087) ``` Signed-off-by: Filinto Duran <1373693+filintod@users.noreply.github.com>
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Fixes #1086.
Motivation and Context
Modern requests are self-contained, so the HTTP protocol-version header cannot make a request valid when the corresponding body _meta is incomplete. Previously, these requests reached tool handlers and returned successful responses.
Reject direct Streamable HTTP requests that select the 2026-07-28 protocol through the MCP-Protocol-Version header but omit required request metadata. Validation now returns HTTP 400 with JSON-RPC -32602 before dispatch, and regression coverage exercises direct tools/list, direct tools/call, and individually missing metadata fields.
How Has This Been Tested?
Add tests
Both suites pass. Focused Clippy checks, including clippy::perf, also pass for the changed targets.
Breaking Changes
None.
Validation remains at the Streamable HTTP boundary so initialized legacy sessions retain their existing behavior. clientInfo remains optional for 2026-07-28, matching the final specification; the tests explicitly preserve that behavior.
Types of changes
Checklist