Claude Code 2.1.323 adds a Code Mode that writes JavaScript to call tools

A coding agent reads ten files and writes three edits. That is thirteen separate tool calls in the normal course of work. Claude Code 2.1.323 lets Claude write one piece of JavaScript that does the same thirteen actions.

Anthropic released Claude Code 2.1.323 to subscribers on 12 November 2026. The release notes say Code Mode is "an experimental opt-in in which Claude writes JavaScript to call its tools". A user turns it on at a documentation page Anthropic links in the notes. An organisation can turn it off for everyone. The usual tool call stays the default. Code Mode is a new shape for the same work.

What else moves in this release

Plugins now carry a supported Claude Code version range in plugin.json. The release notes say plugins outside their stated range are not installed, updated or loaded. Install and update pick the newest version that fits. A plugin author can now release a change that only runs on a recent Claude Code. Older installs do not break. claude plugin validate runs TypeScript type checking on a plugin's hook modules.

Managed settings gain CLAUDE_CODE_AUTO_MODE_MODEL. An admin can set which model Auto Mode calls in Claude Desktop sessions. The setting applies once Claude Desktop includes this release.

A new progress heartbeat fires every 30 seconds while a hook runs long. Anthropic says this stops a host such as Claude Desktop from ending the turn as hung. The old behaviour was a source of lost work on slow checks. The Artifact tool now accepts .docx uploads.

For a model ID Claude Code does not recognise, the assumed context window moves from 200K to 1M tokens. A session close to that limit can call /autocompact by hand. Setting CLAUDE_CODE_DISABLE_1M_CONTEXT=1 keeps the old 200K default.

The safety fixes

Five sandbox and permission fixes land in the same release. A Bash allow rule with an attached wildcard like Bash(ls*) was skipping the permission prompt in some cases. A rule naming a variable like Bash(NODE_ENV*) now asks. The Bash sandbox could leave the legacy config file exposed on older installs. Sandboxed commands could read Claude Code's own file checkpoint copies under the config directory.

Git worktree changes tighten on macOS and Linux. git worktree add, move and remove now fail under the read-only sandbox. Commits in a worktree the session was not started in, or was not given, also fail, even inside the project. The Write and Edit tools no longer write to a path that a Read deny rule covers.

What a team should decide first

Code Mode changes the shape of a session. That makes it a decision, not a default. A script that calls tools is harder to audit step by step than a stream of single calls. A session that produces a long script can also fail further down the script than a single tool call would.

The release notes say Code Mode is experimental and opt-in. A careful team can leave it off on sensitive work. Where the batching pays back, it can be switched on for that project alone.

Source

Release v2.1.323, Anthropic.