- PluginEntry no longer carries save_file: postcard is positional and existing
messages keep their fields (docs/collab-protocol.md), so mixed app/server
versions keep reading the directory. Manage plugins still shows "can save files".
- save_file checks the data length before reading it and refuses with status 1
and the reason, as documented, instead of failing the run with a limit error.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Plugins can hand the host a file name, MIME type and bytes through the new
`save_file` import (plugin API 4, `permissions.saveFile`). The host asks the
user where to save (browser download on the web), so the plugin never sees a
path. Includes the SDK wrapper and the `export-names` example plugin.
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
Assisted-by: Claude (Anthropic)
