Group of 2 Use it now
Claude Code now ships built-in 'diff' and 'claude-test' plugins, loaded through a new lazy plugin-loading mechanism
What
- Two new built-in plugin bundles, named
diffandclaude-test, are now loaded alongside the existing built-in plugins (sec-default,agents-md,plugin-authoring,tips). - The
claude-testplugin adds skills (claude-test,claude-test-execute,claude-test-draft), agents (explorer,author,runner), and a browser automation server so Claude Code can run plain-language specs from.claude-test/specs/against your local dev server in a real headless browser and report pass/fail results with screenshots, via a new/claude-testcommand. - Built-in plugin registration itself was refactored from immediate registration calls into a named, lazy-loading pattern.
Why This adds a ready-to-use way to write and run browser-based tests for your app directly from Claude Code, without installing a separate plugin.
Names in the bundlediffclaude-test
The entry above is what we published on the day. These lines were added later, as Anthropic's own pages caught up, and they sit beside the original rather than replacing it.
Added since
A small documentation edit on Use Claude Science on more than one computer touched a line naming diff after this was published.
Claude Science keeps the work from each sign-in in its own folder on your computer. When you sign in to a different organization or personal account on that computer (for example, a Team plan after a personal plan), a banner at the top of …claude-science/multiple-computers see the edit
Confirmed since
Anthropic's documentation has since written up diff, on Claude Code changelog.
* Fixed fullscreen mode freezing or blanking for several seconds when scrolling up past a large file diffchangelog see the edit
Something disagreesSomething we can check disagrees with this entry, or the writer said they could not settle it.
The writer flagged doubt
The finding doesn't say what the 'diff' or 'claude-test' plugins actually do, or whether lazy loading changes startup behavior noticeably.
Anthropic's documentation agrees
Anthropic's documentation has since written up diff, on Claude Code changelog.