Source Intelligence

DisclaimerUnofficial, and not affiliated with Anthropic. Nearly all of this is read straight out of what ships: npm bundles, captured prompts, published docs. Anthropic's own notes go in verbatim, marked as theirs. The rest is my reading, and every entry carries the strings behind it. If one looks wrong, vote it down and say why.

All of v2.1.227 Home All releases olderv2.1.226 v2.1.228newer
Claude Code v2.1.227

MCP connection timeouts are reported as timeouts

You'll notice
Useful3 Signal1
MCP

A slow MCP server is now reported as a timeout rather than a vague connection failure.

Feature flag
tengu_mcp_connect_timeout_retry Not enough to say

Nothing here resolved what this flag was doing on this version, so nothing here should be read as on or off.

This account: no value returned · anonymous baseline: no value returned · compiled default in v2.1.227: off

These values were read against a different version of Claude Code, so treat them as the nearest reading available instead of one taken on this release.

Read once, for one account on one subscription tier, against v2.1.227. It isn't a statement about your account. What a flag value here can and cannot tell you

What

An MCP server that fails to connect because it timed out is now labelled with its own CONNECT_TIMEOUT code instead of being lumped in with generic failures, so the Connection failed message tells you the server was too slow rather than unreachable or misconfigured.

Details
  • A timeout from the MCP SDK during connect is reclassified to this code, which joins the existing set of MCP failure codes such as ENDPOINT_NOT_FOUND and AUTH_HEADER_REJECTED.
  • Emits mcp_connect_failed telemetry with reason: "timeout".
  • Paired with tengu_mcp_connect_timeout_retry, which falls back to on; with no server value the timeout tagging is active.
Evidence

CONNECT_TIMEOUT, Object.assign(t, { code: "CONNECT_TIMEOUT" }), mcp_connect_failed

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

See this entry in the whole of v2.1.227 →