fix(auth): check token expiry before scopes in withMcpAuth - #182
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anshusaurav wants to merge 1 commit into
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fix(auth): check token expiry before scopes in withMcpAuth#182anshusaurav wants to merge 1 commit into
anshusaurav wants to merge 1 commit into
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An expired token that also lacked a required scope was reported as 403 insufficient_scope instead of 401 invalid_token. Per RFC 6750 §3.1 an expired token is always invalid_token — this matters because clients use the error code to decide whether to refresh the token or surface a permissions error. Move the expiresAt check above the requiredScopes check so expiry is evaluated first. Add regression tests covering both orderings. Fixes vercel#181
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allenzhou101
approved these changes
Aug 6, 2026
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Summary
401 invalid_tokeninstead of403 insufficient_scopeexpiresAtcheck above therequiredScopescheck inwithMcpAuthso expiry is always evaluated first, per RFC 6750 §3.1Fixes #181
Why it matters
401 invalid_tokentells an MCP client its token is no longer valid — the client should refresh or re-authenticate.403 insufficient_scopetells the client it has the wrong permissions — the client will not refresh and may surface a misleading "insufficient permissions" error. When both conditions are true, RFC 6750 requires the expiry to win.Test plan
invalid_token(was 403 before fix)insufficient_scope(unchanged)vitest run)