Reading a new releasev2.1.251Analysing changes · 2/5Sorting the findings · 1/4 steps470 findings$18.91 so far
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.
When a model rejects a thinking type, Claude now logs the rejection and can retry with a different configuration: "[thinking] model rejected thinking.type={type}".
Evidence
Thinking type retry (search for "retry:thinking-type", "[thinking] model rejected thinking.type=")
Strings lifted out of the shipped bundle, so the claim above can be checked against them.
