10 Claude Mods to Build

Mods are small JavaScript or TypeScript functions that change how Claude Code looks and behaves. In the terminal they need Claude Code v2.1.287 or later, and they also work in the Code tab of the desktop app.

The simplest way to build one is to describe it in a Claude Code session. Claude writes the mod, loads it, and reloads it each time you request a change.

Start small. A mod that does one job well makes a great first mod.

Make a mod that displays context window usage as a percentage above the prompt, refreshed after every turn, turning yellow above 60% and red above 85%.

Make a mod that pauses Bash commands matching rm -rf, git reset --hard, or git push --force, explains what each one would change, and shows Proceed and Cancel buttons.

Make a mod that adds a /note command, which appends my text and the current time to notes.md in this project without starting a Claude turn.

Make a mod with a /focus command that starts a 25-minute timer displayed above the prompt, then reminds me to review the changes when it ends.

• Launch Claude Code inside a practice folder
• Paste in the prompt and allow hot reloading
• Try the mod on real tasks
• Request one change at a time
• Copy the mod folder somewhere safe, since a session mod loads only in that session
• Install the mod from a marketplace to use it everywhere

• Run claude plugin validate to catch errors
• Keep data in the mod’s state so it survives reloads
• Run claude --debug when a mod does nothing
• Write tests with claude plugin test

• Remember that mods run with your permissions and have no sandbox
• Never hardcode API keys into a mod
• Never let a mod approve tool calls you have not thought through
• Read every line of a mod before you share it
• Install mods from other people only when you trust the source

Mods are plugins, so you can share them through a plugin marketplace hosted in a Git repository or submit them to the Claude directory.