Claude Code adds TypeScript mods for custom behavior and UI
Anthropic says Claude Code mods are TypeScript functions packaged in plugins. They can rewrite prompts, intercept tool calls, change the interface, and replace built-in features. Mods are available in the Claude Code CLI and desktop app.
SessionWatcher editorial · Published · Updated · Source announcement: 2026-10-01
Related guide: How to check your Claude Code usage
What Claude Code mods can do
Anthropic announced mods, small TypeScript functions that change how Claude Code works. A mod can rewrite a prompt, add new UI, replace a built-in feature, or add functionality. Mods ship inside plugins, so users can install and share them like other plugins.
Mods hook into Claude Code events, running before, after, instead of, or around an event. They can block, rewrite, or retry tool calls; approve or deny permission requests; and redact secrets from tool output before Claude reads it. They can also edit or replace interface elements and add buttons and inputs.
Sources: Customize Claude Code with mods
Availability and safety
Mods work in the Claude Code CLI and desktop app. Users can ask Claude Code to write a mod, install it, and hot reload it in the session. The built-in /diff feature is now a mod that users can turn off or replace.
Mods have the same access to a machine as Claude Code and are not sandboxed. Anthropic says to install only mods from trusted sources. On Team and Enterprise plans, owners control plugin marketplaces, and a built-in security mod loads first unless admins choose to load their own mods first.
Sources: Customize Claude Code with mods
AI assisted reporting, checked against the linked official sources. Source pages checked 2026-10-03. Editorial process and corrections.