Sweep 19 Sep 2026 · 02:36Z Build v2.1.278 500 read Stable v2.1.267 Latest v2.1.278 Next v2.1.278 Feeds RSS JSON llms.txt Unofficial
Claude Code v2.1.275 ·

OpenTelemetry header helper: prefetching and failure warnings

Claude Code now prefetches your custom OpenTelemetry header helper for HTTP exporters and warns you if it fails

TierYou'll noticehow much it should matter to you
Useful3my rating, 1 to 5
Signal2worth watching, 1 to 5
AreaTelemetrywhat it touches
KindImprovementsin v2.1.275,
Group of 2 You'll notice

Claude Code now prefetches your custom OpenTelemetry header helper for HTTP exporters and warns you if it fails

What

  • For OpenTelemetry (OTel, a standard for exporting telemetry data) exporters using HTTP-based protocols (http/json or http/protobuf), a user-configured otelHeadersHelper is now prefetched once per process to prime its cache, instead of being fetched lazily on the first request.
  • If otelHeadersHelper fails, Claude Code now shows a dismissible warning notification (visible for 30 seconds) telling you that telemetry is not being exported and to check /status for details.

Why

Prefetching avoids a delay on the first telemetry request, and the new warning makes it clear when your custom header helper is broken instead of silently dropping telemetry exports.

Read from
Names in the bundle/status
Feature flag
tengu_quirky_teacup 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 v2.1.275: on

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 v2.1.275. It isn't a statement about your account. What a flag value here can and cannot tell you

What the documentation says
/status Claude Code changelog modified, high confidence * Fixed `/status` not showing the `apiKeyHelper` failure that its own error banner told you to check see the edit
/status Changelog modified, high confidence * Fixed the Code tab's `/status` card showing a placeholder account; it now shows your signed-in identity and the deployment name. see the edit
/status Deploy managed settings modified, high confidence When an admin source sets `allowManagedMcpServersOnly` or an `allowedMcpServers` list and that value isn't the one in force, `/status` and `claude doctor` name that source and key. see the edit
Since it was published

The entry above is what we published on the day. These lines were added later, as Anthropic's own pages caught up, and they sit beside the original rather than replacing it.

Added since A small documentation edit on Manage costs effectively touched a line naming /status after this was published. For a response from the Claude API billed at the 1.1× [data residency rate](https://platform.claude.com/docs/en/about-claude/pricing#data-residency-pricing), Claude Code multiplies the list price of that response's tokens by 1.1 in the ses… costs see the edit
Confirmed since Anthropic's documentation has since written up /status, on Claude Code changelog. * Added an `Auto mode server` row to `/status` showing whether this session's auto mode classifier runs on the server changelog see the edit
How sure we are
Two sources agreeTwo things we can check say the same as this entry.
Anthropic's documentation agrees/status on Claude Code changelog
Anthropic's release notes agreeAdded the signed-in account to Claude apps gateway sign-in: when the gateway names it, you confirm it before the credential is saved, and…
The name it cites is new in this buildNew in this build: tengu_quirky_teacup

See this entry in the whole of v2.1.275 →