What
A new preview action on the artifact tool renders a local .html file in a headless browser at one or more viewport widths and in both light and dark themes, and returns screenshots plus a list of problems found by static checks. It asks permission first. Nothing is uploaded, though the page can still fetch any Google Fonts stylesheets it references.
Details
- The result carries the captures, the issue list, a count of issues that were dropped, and a render error when one occurred, so a browser that fails to start is reported instead of quietly producing nothing.
- If the browser cannot launch, the static checks still run on their own and the first line of the result explains why rendering did not happen.
- The
widthsandthemesparameters only appear on the tool's inputs when the same shape check that decides which artifact actions are offered is satisfied. That check is derived from the artifact tool's action list rather than a compiled-in on/off value, so whether preview is offered to a given account is decided by that list.
Evidence
The browser could not start, so nothing was rendered and only the static checks ran; the first line below says why.
Strings lifted out of the shipped bundle, so the claim above can be checked against them.
Names in the bundlepreview
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 Commands touched a line naming preview after this was published.
| `/import [codex\|gemini\|cursor] [--dry-run] [--yes]` | Bring configuration from OpenAI Codex, Google Gemini CLI, or Cursor on your machine into Claude Code, including instruction files, MCP servers, commands, subagents, and skills. In […commands see the edit
Confirmed since
Anthropic's documentation has since written up preview, on Run on a remote Linux server.
| Interactive HTML previews render as static snapshots after a short delay (charts don't respond) | The tunnel isn't forwarding the preview port. Add the second `-L` forward; the preview port is the web app port plus one (8001 by default).…claude-science/run-on-remote-linux-server see the edit
One source agreesOne thing we can check says the same as this entry.
Anthropic's documentation agrees
Anthropic's documentation has since written up preview, on Run on a remote Linux server.