Advanced Hook Use Cases

This reference covers advanced hook patterns and techniques for sophisticated automation workflows.

Multi-Stage Validation

Combine command and prompt hooks for layered validation:

{
  "PreToolUse": [
    {
      "matcher": "Bash",
      "hooks": [
        {
          "type": "command",
          "command": "bash ${CLAUDE_PLUGIN_ROOT}/scripts/quick-check.sh",
          "timeout": 5
        },
        {
          "type": "prompt",
          "prompt": "Deep analysis of bash command: $TOOL_INPUT",
          "timeout": 15
        }
      ]
    }
  ]
}

Use case: Fast deterministic checks followed by intelligent analysis

Example quick-check.sh:

#!/bin/bash
input=$(cat)
command=$(echo "$input" | jq -r '.tool_input.command')

# Immediate approval for safe commands
if [[ "$command" =~ ^(ls|pwd|echo|date|whoami)$ ]]; then
  exit 0
fi

# Let prompt hook handle complex cases
exit 0

The command hook quickly approves obviously safe commands, while the prompt hook analyzes everything else.

Conditional Hook Execution

Execute hooks based on environment or context:

#!/bin/bash
# Only run in CI environment
if [ -z "$CI" ]; then
  echo '{"continue": true}' # Skip in non-CI
  exit 0
fi

# Run validation logic in CI
input=$(cat)
# ... validation code ...

Use cases:

• Different behavior in CI vs local development
• Project-specific validation
• User-specific rules

Example: Skip certain checks for trusted users:

#!/bin/bash
# Skip detailed checks for admin users
if [ "$USER" = "admin" ]; then
  exit 0
fi

# Full validation for other users
input=$(cat)
# ... validation code ...

Hook Chaining via State

Share state between hooks using temporary files:

# Hook 1: Analyze and save state
#!/bin/bash
input=$(cat)
command=$(echo "$input" | jq -r '.tool_input.command')

# Analyze command
risk_level=$(calculate_risk "$command")
echo "$risk_level" > /tmp/hook-state-$$

exit 0

`