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 v2.1.242 Home All releases olderv2.1.241 v2.1.243newer
Claude Code v2.1.242

Clearer error when an effort level needs thinking turned on

Use it now
Useful3 Signal3
Effort

You now get told when an effort level needs thinking on, and what turned thinking off.

MAX_THINKING_TOKENSalwaysThinkingEnabled
What

A new error branch explains that the effort level you picked is not available with thinking turned off on this model, tells you to raise effort or re-enable thinking, and names what disabled thinking: the MAX_THINKING_TOKENS environment variable, the alwaysThinkingEnabled setting, or the way the session was started.

Details
  • Triggered by the shape of the API error, so it applies wherever the request is made from.
Evidence

isn't available with thinking turned off on this model

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 v2.1.242 →