The brief
Claude Code 2.1.321 adds Claude Fable 5.2 as its default Fable model, according to Anthropic's release notes. The same release adds a --settings file option to remote control, which applies a settings file to each session started there. When that file changes, remote control must be restarted before new sessions use it. The release also lists changes to saved model selections and fast-mode labels, so teams with a pinned model choice should review the original notes.
The security-related fixes are more important than the version number. Anthropic says MCP OAuth requests no longer send secrets such as refresh tokens to another host after a server redirect. It also fixes cases where a read-only Bash command ran outside the sandbox without a prompt, and where write permission checks used the wrong folder. These are distinct fixes; the release notes give the precise affected behaviors. Updating is especially relevant for users who connect MCP servers or rely on command permission prompts.