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

Stale-data refetch throttle becomes server-tunable, still off by default

Not switched on
Useful1 Signal2
Internals

Refetch throttling after stale-data signals is now server-tunable but stays off without a server value.

tengu_expressive_whistle compiles in false, so the throttled refetch path never runs.

Feature flag
tengu_expressive_whistle Off in both readings

The flag server returned off for the account this site reads and for the anonymous baseline. A reading of off cannot rule out a rollout these two readings sit outside of.

This account: off · anonymous baseline: off · compiled default in v2.1.248: on

Read once, for one account on one subscription tier, against v2.1.248. It isn't a statement about your account. What a flag value here can and cannot tell you

What

When the server signals that Claude Code's cached client data is out of date, the refetch is rate-limited. Those limits moved from fixed values to a server-supplied config, tengu_expressive_whistle_config: a minimum interval defaulting to 300 seconds (clamped 30 to 86400) and jitter defaulting to 180 seconds (clamped 0 to 3600). The whole path sits behind tengu_expressive_whistle, whose compiled fallback is false, so without a server value it never runs.

Details
  • Both resolved values are reported in the refetch event as min_interval_ms and jitter_ms.
  • The config key defaults to an empty object, so the defaults above apply if the gate is turned on without config.
Evidence

tengu_expressive_whistle_config

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

See this entry in the whole of v2.1.248 →