fix get_client_metadata_scopes on 401 #1631
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Thank you for this fix! I've gone ahead and added a unit test which fails on main just to confirm the fix. |
This test verifies that when a 401 response contains both resource_metadata and scope in the WWW-Authenticate header, the actual scope is used instead of incorrectly using the resource_metadata URL. Github-Issue:modelcontextprotocol#1630
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Co-authored-by: Max Isbey <224885523+maxisbey@users.noreply.github.com>
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This PR fixes an issue where the OAuth2 client passed the protected-resource URL as the
scopevalue during token requests. The implementation now correctly uses the parsedscope(orNonewhen no scope is provided).Fix #1630
Motivation and Context
The previous behavior incorrectly substituted the OAuth protected-resource URL for the
scopeparameter, leading to malformed token requests and potential authorization failures. By ensuring that the correct scope is passed, OAuth2 flows behave as expected and remain compliant with spec and provider expectations.How Has This Been Tested?
The fix was tested against an OAuth2 provider in a real application environment. Token requests were validated to ensure that:
Breaking Changes
No breaking changes. This is a bug fix that restores correct behavior and should not require user code changes.
Types of changes
Checklist
Additional context
The problematic logic was located around the OAuth2 request-building code near lines 508–512, where the URL was incorrectly forwarded as the scope. The updated implementation ensures correct scope derivation and preserves compatibility with standard OAuth2 servers.