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All of v2.1.248 Home All releases olderv2.1.247 v2.1.250newer
Claude Code v2.1.248

Separate failure code when a credential helper's token is rejected

You'll notice
Useful3 Signal2
MCP

A rejected credential-helper token is now reported as its own MCP failure with clearer advice.

headersHelper
What

A 401 or 403 from an MCP server whose Authorization header came from a configured headersHelper command is now reported as its own failure, severity "bad", rather than being lumped in with a static auth header rejection. The message tells you OAuth fallback is disabled when the helper supplies Authorization.

Details
  • Reported and telemetered as mcp_connect_headers_helper_auth_rejected, alongside the existing static-header, CLI-bearer and first-party rejection codes.
  • Message text: "Server rejected the Authorization header minted by the configured headersHelper".
Evidence

mcp_connect_headers_helper_auth_rejected, Server rejected the Authorization header minted by the configured headersHelper

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Related

Other releases about the same thing. Found by shared names or similar wording; neither means one caused the other.

See this entry in the whole of v2.1.248 →