fix(mcp): keep OAuth challenges at HTTP boundary - #529
Draft
matoous wants to merge 1 commit into
Draft
Conversation
The MCP adapter converted downstream SumUp API 401 responses into JSON-RPC InternalError values containing a pseudo WWW-Authenticate field. MCP clients require a real HTTP 401 challenge and cannot discover OAuth from that tool-level error. Remove the nonstandard conversion, preserve the original SDK error, deprecate the ineffective resource options, and document transport-boundary bearer validation and authInfo propagation.
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
1 participant
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
What changed
401conversion into JSON-RPCInternalErrorauthInfopropagation for remote transportsWhy
MCP OAuth discovery requires an HTTP
401response with aWWW-Authenticateheader. A tool-level JSON-RPC error carrying a similarly named data property cannot trigger the client authorization flow and incorrectly claimed protocol compliance.Impact
The toolkit no longer emits a nonstandard OAuth representation. Remote HTTP deployments have an explicit contract to reject invalid credentials before MCP dispatch and pass validated tokens through request auth context.
Validation
npm --prefix typescript run lint:fixnpm --prefix typescript test -- --runInBandSpecification reference: https://modelcontextprotocol.io/specification/2025-11-25/basic/authorization