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.

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Claude Code v2.1.229

/prototype now picks a fidelity and can build on an app you already have

Use it now
Useful4 Signal3
Skills not in their notes

/prototype picks a fidelity itself, can build on your existing app, and hands off a scoped brief.

/prototype
What

The prototype skill names three fidelities, sketch, clickable and wired, defaults to clickable, and states its pick instead of asking you. If you explicitly ask, it can prototype a feature on top of an existing app, either as a screenshot overlay or a shell built from your repo source. A new hand-off step converts the finished prototype into an approved brief split into must-have, nice-to-have and cut.

Evidence

Every prototype is built at one of three fidelities, and naming it sets

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 v2.1.229 →