Anthropic adds JavaScript and TypeScript mods to Claude Code

Anthropic introduced mods for Claude Code — small JavaScript and TypeScript functions that hook into events inside the tool. They can rewrite prompts, block or rewrite tool calls, handle permissions and replace parts of the interface; mods are enabled by default in Claude Code 2.1.287 and later and ship as plugins.

• Mods hook into Claude Code events and can rewrite prompts and tool calls
• The feature is on by default in Claude Code 2.1.287 and later
• Mods are distributed as plugins, including via GitHub repositories
• Anthropic already uses mods for AGENTS.md support and the /diff pane