Source Intelligence
Follow Discord

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 v2.1.228 Home All releases ←olderv2.1.227 v2.1.229newer→
Claude Code v2.1.228

Fallback models are reflected in the reported model

You'll notice
Useful4 Signal3
Models

If a request falls back to another model, you now see the model that actually answered.

What

When a request falls back to a different model mid-stream, the model shown to the client now matches the one that actually answered.

Details
  • A streamed content block of type "fallback" sets the accumulated message's model to the fallback target.
  • The gateway's event re-encoder rewrites the model on the opening message_start event when an override model is in play.
Evidence

content_block.type === "fallback"

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 v2.1.228 →