Under the hoodTier: how much it should matter to you
2Useful: my rating, 1 to 5
2Signal: worth watching, 1 to 5
MCPArea: what it touches
Internal ChangesKind: in v2.1.248,
Internal ChangesSection of the release
What
Failure reports for sse, http and claudeai-proxy MCP transports now carry a field marking headers minted by a credential helper, alongside the existing user-header and CLI-bearer flags. It feeds the same classifier behind tengu_mcp_server_connection_failed. Unconditional.
Evidence
helperMintsAuthHeader
Strings lifted out of the shipped bundle, so the claim above can be checked against them.