Project tool can read original uploads and refuse stale writes

What

The project tool lets Claude read and write the documents in an attached claude.ai Project. It gains two options.

• project_read with original: true saves the original file of an uploaded document, such as a PDF or docx, to a local file and returns its path instead of the extracted text. The option is ignored for text docs and other uploads.
• project_write accepts if_version, the 64-character version hash (SHA-256) that came with the copy Claude worked from, and returns a new version. If the doc has changed since, the write fails with project_doc_stale.
• A badly formed if_version is rejected with: "Nothing was changed. if_version must be the 64-character version that came with the copy you worked from, copied exactly. If you do not have it, project_read the doc. Omit it for a new doc."
• The tool description gains matching passages, shown only when the options apply. Tool names in the text are now filled in automatically, and the tool gains coerceInput handling.
• The file-not-found error now says that synced sources, such as GitHub and Google Drive, are not listed.

Both options depend on the gate tengu_mossy_wirth, which falls back to false. original also needs a non-zero session file limit. When an option is not available, it is removed from the tool's input, and a call that includes it gets a note such as "Note: original is not available in this session and was ignored." or "Note: if_version is not available in this session and was ignored: this call did not check whether the doc had changed." For tengu_mossy_wirth, the flag server returned off for this site's account and for the anonymous baseline, and no reading has been taken under this release yet.

Why

Where the options are available, Claude cannot overwrite a project doc that someone else changed after Claude read it. Claude can also work with the real PDF or docx instead of only its extracted text.