# With validator function
    Agent(guardrails=my_validator_fn)
    
    # With string preset
    Agent(guardrails="strict")  # Uses strict preset

    # For tool policy enforcement, use the dedicated `policy` param instead:
    Agent(policy=PolicyEngine(...))  # policy strings on guardrails are NOT enforced

    # With config
    Agent(guardrails=GuardrailConfig(
        validator=my_validator_fn,
        max_retries=3,
        on_fail="retry",
    ))
    
    # With LLM-based validation
    Agent(guardrails=GuardrailConfig(
        llm_validator="Ensure response is helpful and safe",
        max_retries=2,
    ))