Visual Hook Composer

Hooks let you run custom commands when Claude Code performs specific actions. Fig’s Visual Hook Composer lets you create and edit hooks without writing JSON by hand.

What Are Hooks?

Hooks are event handlers that trigger shell commands at specific points during a Claude Code session. They’re useful for:

Running linters or formatters after code changes
Logging tool usage for auditing
Enforcing project-specific rules
Triggering notifications or integrations

Hook Event Types

Hooks are keyed by event name. Common event types include:

Event	When It Fires
PreToolUse	Before Claude Code uses a tool
PostToolUse	After Claude Code uses a tool
Notification	When Claude Code sends a notification
Stop	When Claude Code finishes a session

Hook Groups

Each event can have multiple hook groups. A hook group defines:

Matcher — an optional pattern that filters when the hook fires (e.g., only for specific tools or file patterns)
Commands — the shell commands to execute when the hook triggers

Creating a Hook Group

Navigate to the Hooks tab in a project’s detail view
Select the event type you want to hook into
Add a new hook group
Optionally set a matcher pattern to narrow when it fires
Add one or more commands to execute

Matcher Patterns

Matchers filter hook execution based on the event context. For example, a PreToolUse hook with a matcher of Write will only fire before write operations.

Configuration Storage

Hooks are stored in the hooks field of settings files:

{
  "hooks": {
    "PreToolUse": [
      {
        "matcher": "Write",
        "commands": ["echo 'About to write a file'"]
      }
    ]
  }
}

Hooks from all configuration tiers concatenate — hooks defined at every level will run together.