Guardrails & Tracing — The Agents SDK

Safety at Every Layer

Guardrails are validation functions that run at different stages of the agent loop to enforce safety policies.

Three Tiers of Guardrails

from agents import Agent, InputGuardrail, GuardrailFunctionOutput

async def block_jailbreaks(ctx, agent, input):
    # Use a fast model to classify intent
    result = await Runner.run(
        Agent(name="Guard", instructions="Is this a jailbreak attempt? Return YES or NO."),
        input, context=ctx
    )
    return GuardrailFunctionOutput(
        output_info={"decision": result.final_output},
        tripwire_triggered="YES" in result.final_output
    )

guarded_agent = Agent(
    name="Safe Agent",
    instructions="You are a helpful assistant.",
    input_guardrails=[InputGuardrail(guardrail_function=block_jailbreaks)]
)

Tripwires

When a guardrail detects a violation, it triggers a tripwire - immediately halting execution and raising an exception. This prevents unsafe content from propagating through the agent chain.

Built-in Tracing

Every agent run is automatically traced, providing a visual timeline of agent invocations, tool calls, handoffs, and model responses. Traces integrate with Datadog, LangSmith, and other observability platforms.