fix: pass new conformance auth scenarios, bump to 0.1.13#1999
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fix: pass new conformance auth scenarios, bump to 0.1.13#1999
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…stered credentials Two conformance auth scenario fixes: 1. Resource mismatch validation (RFC 8707): After discovering Protected Resource Metadata, validate that the resource field matches the server URL before proceeding with authorization. If the PRM returns a resource from a different origin, raise OAuthFlowError. 2. Pre-registration fallback: When Dynamic Client Registration fails (e.g. server returns 404), fall back to pre-registered client credentials from storage instead of crashing. The conformance client now pre-loads client credentials from MCP_CONFORMANCE_CONTEXT when available.
The _initialize() method already loads client_info from storage before the OAuth flow runs. When pre-registered credentials are in storage, the 'if not self.context.client_info' guard skips DCR entirely — no fallback needed.
Pydantic AnyHttpUrl adds a trailing slash to root URLs (e.g. "https://example.com/") while resource_url_from_server_url may return without one. This caused check_resource_allowed to reject valid root-URL servers due to path length mismatch.
Code reviewNo issues found. Checked for bugs and CLAUDE.md compliance. |
Kludex
reviewed
Feb 5, 2026
| ) | ||
| ) | ||
| logger.debug(f"Pre-loaded client credentials: client_id={client_id}") | ||
| except json.JSONDecodeError: |
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Dont you want to see the exception if the json is wrong?
Allows clients to override or disable PRM resource validation. Called with (server_url, prm_resource) and can raise to reject, return to accept, or implement custom logic. When not provided, default behavior validates per RFC 8707 and rejects mismatches.
The tests used a PRM resource (https://api.example.com/mcp) that didn't match the server URL (https://api.example.com/v1/mcp). This was silently ignored before resource validation was added.
Tests for resource mismatch rejection, matching resources, custom callback override, and root URL trailing slash normalization.
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Fixes the conformance CI build which was broken by
@modelcontextprotocol/sdk@1.26.0being resolved as a transitive dependency of the conformance package.Changes
SDK fix — PRM resource validation (RFC 8707):
After discovering Protected Resource Metadata, the OAuth client now validates that the
resourcefield matches the server URL before proceeding with authorization. If the PRM returns a resource from a different origin (e.g.https://evil.example.com/mcp), the client raisesOAuthFlowErrorinstead of blindly continuing the auth flow.Conformance client — pre-registration support:
The conformance test client now pre-loads client credentials from
MCP_CONFORMANCE_CONTEXTinto token storage when available. This allows the existing_initialize()flow to skip DCR when pre-registered credentials are present, which is the correct behavior per the MCP spec's pre-registration approach.CI — bump conformance to 0.1.13:
Updates from
@modelcontextprotocol/conformance@0.1.10to0.1.13which includes thetools_callscenario fix for SDK 1.26.0 compatibility.