Claude Code Hooks & Automation

{
  "hooks": {
    "preCommand": [
      {
        "command": "echo 'Starting operation...'",
        "description": "Log operation start"
      }
    ],
    "postCommand": [
      {
        "command": "npm run lint -- --fix",
        "description": "Auto-fix lint issues after changes",
        "onFailure": "warn"
      },
      {
        "command": "npm run typecheck",
        "description": "Verify TypeScript types after changes",
        "onFailure": "error"
      }
    ]
  }
}

preCommand   — Runs BEFORE Claude executes a tool
postCommand  — Runs AFTER Claude executes a tool
onError      — Runs when Claude encounters an error
onFileChange — Runs when Claude modifies a file

{
  "hooks": {
    "postCommand": [
      {
        "command": "npm test -- --related",
        "description": "Run related tests after file changes",
        "condition": "fileChanged",
        "glob": "src/**/*.ts"
      }
    ]
  }
}

#!/bin/bash
# .claude/hooks/validate-changes.sh
# Run after Claude modifies files

# Check for console.log statements
if grep -r "console.log" src/ --include="*.ts" --include="*.tsx"; then
  echo "ERROR: console.log found in source files"
  exit 1
fi

# Check for any type usage
if grep -r ": any" src/ --include="*.ts" --include="*.tsx"; then
  echo "WARNING: 'any' type detected — consider using specific types"
fi

echo "Validation passed"

{
  "postCommand": [{
    "command": "npx prettier --write .",
    "condition": "fileChanged",
    "glob": "**/*.{ts,tsx,json}"
  }]
}

{
  "postCommand": [{
    "command": "npx jest --findRelatedTests $(git diff --name-only)",
    "condition": "fileChanged",
    "glob": "src/**/*.ts"
  }]
}