tengu_api_success

A Claude Code feature flag, read out of the shipped bundle. No mined inventory carries it: everything below comes from what this site has written about it.

Releases whose published page names tengu_api_success.

1. v2.1.281 23 Sep 2026
   tengu_api_success gains a dispatch field

   Usage data for API calls now includes a dispatch value, which defaults to "none"

   found in this entry's text

2. v2.1.281 23 Sep 2026
   Side-query dispatch-header fallback broadened, and dispatch recorded on success

   A failed side query can now be resent once with a fixed dispatch value in more cases, including 503s, timeouts, conflicts and rate limits

   found in this entry's text

3. v2.1.274 16 Sep 2026
   New telemetry field arm_source on refusal and API events

   Telemetry for refusals and API success events now records which experiment arm produced the response

   gate cited by this entry, found in this entry's text

4. v2.1.274 16 Sep 2026
   tengu_api_success gains tender_quilt_header flag

   tengu_api_success telemetry gains a tender_quilt_header flag for low-priority background requests

   gate cited by this entry, found in this entry's text

5. v2.1.268 10 Sep 2026
   tengu_api_success gains firstContentMs, clientRequestId, user_message_uuid

   API success telemetry now records time-to-first-content, a client request id, and the user message's UUID

   gate cited by this entry, found in this entry's text

6. v2.1.268 10 Sep 2026
   API dispatch requests now carry a per-attempt client request ID and richer retry telemetry

   API requests now carry a per-attempt request ID and log more detail about retries

   gate cited by this entry

7. v2.1.263 6 Sep 2026
   New thinkingPrefixMismatchBehavior field on API telemetry, tied to a 'block_binding' beta feature

   API telemetry can now log a thinking-block mismatch setting, but only under a specific unreleased beta header.

   found in this entry's text, gate cited by this entry

8. v2.1.257 1 Sep 2026
   New tengu_tool_schema_sizes telemetry event with dedup cache

   A new event breaks down tool schema sizes by category, deduplicated and capped at 512 hashes.

   found in this entry's text, gate cited by this entry

9. v2.1.233 14 Aug 2026
   API result telemetry carries the proactivity level

   API success and error telemetry now includes your session's proactivity level.

   gate cited by this entry, found in this entry's text

No release here has a gate table behind it for this flag. Most published releases have none at all: the readings exist only for versions the pipeline captured flag state on.

The earliest release whose published evidence quoted tengu_api_success was v2.1.233, 14 Aug 2026. That is the oldest release this project wrote about it, so it is a floor on the name's age and not the release that introduced it. It is not a presence reading: which builds carried the name is the table below.

The miner has never read a build containing this name. It is here because a changelog entry of ours names it, which is evidence that it existed and not evidence of which releases carried it. The inventory starts at v2.1.138 and everything older than that was never mined.

Read out of the published npm bundle release by release, and out of Anthropic's own documentation as this site captured it. Nothing on this page is a description anybody here wrote about what the feature flag does. All feature flags.