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New guidance text explains how to safely update artifact documents using version numbers
What
Claude Code has new built-in guidance explaining how to edit "artifact" documents safely when multiple edits might happen. Every time a document is read or written, the response includes a version number. To update the document with update or str_replace, that version must be passed back as if_version. If the document has changed since that version was read, the write is refused and nothing is applied.
Why
This prevents one edit from silently overwriting changes made in between, since a write only succeeds if it's based on the document's current version.
Names in the bundleif_version