You'll noticeTier: how much it should matter to you
2Useful: my rating, 1 to 5
3Signal: worth watching, 1 to 5
ProjectsArea: what it touches
ImprovementsKind: in v2.1.301,
ImprovementsSection of the release
What
project_write is the tool Claude uses to write project documents. Instead of passing a file's text, Claude can point it at a file on disk with local_path. That option changed:
Allowed files: the tool description now says local_path works for a text file of at most 1 MiB that Claude read or wrote in full in this session. It must be under the working directory or one of two other named folders, and the working directory must not be your home folder.
Notebooks: a notebook can no longer be uploaded by local_path. The error tells Claude to pass its text as content instead.
Refused uploads: when an upload is refused, the error now says the file is missing or unreadable, or its location, name or type is not allowed, and suggests passing the text as content. Its code is local_path_other_container_refusal. Before, this fell through to a general message.
The messages for a file that was not read, or has changed since, were reworded.
Why
When an upload by path is refused, Claude gets the actual reason and the fix, so it can pass the text directly instead of guessing.
