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Claude Code v2.1.246

Compaction retries on a fallback model when the summarizer is refused

You'll notice
Useful4 Signal3
Compaction

If compaction's model is refused, it retries on an allowed fallback instead of failing outright.

/model
What

If the API refuses a compaction request and offers a fallback model, compaction now aborts the refused stream and retries on an allowed fallback instead of failing. When your model policy leaves no usable fallback, compaction stops with a message naming the model and pointing at /model.

Details
  • When the API supplies one, a usage-credit code is minted for the fallback model.
  • The retry is recorded as tengu_refusal_fallback_triggered with a query source of "compact".
  • Example failure text: "Compaction unavailable: your model policy only allows Fable 5, which requires usage credits ยท /model to set it up".
Evidence

Compaction unavailable: your model policy only allows Fable 5, which requires usage credits \xB7 /model to set it up

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

Related

Other releases about the same thing. Found by shared names or similar wording; neither means one caused the other.

See this entry in the whole of v2.1.246 →