You'll noticeTier: how much it should matter to you
3Useful: my rating, 1 to 5
1Signal: worth watching, 1 to 5
ToolsArea: what it touches
ImprovementsKind: in v2.1.321,
ImprovementsSection of the release
What
Write is the tool Claude uses to create or replace a whole file. It now refuses when only the beginning of the file was shown in the session, with the message "Only the start of this file was given in this session, so a Write could lose the rest."
Two smaller changes:
Edit checks: the checks the Edit tool makes for a file that already exists or is a Jupyter notebook now run through shared code. The messages are the same.
Connector uploads: when uploading a file to a connector (a link to an outside service) fails, the message now adds that it is unknown whether the file reached the connector.
Why
Replacing a whole file Claude had only partly seen could silently delete the part it never read. That is now blocked.
