What's the difference between guardrails and evals for ai agents, and when should you use each?

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The context provided doesn't define guardrails or evals for AI agents. It lists your identity, assets, toolkits, and flows. I have to use general knowledge to answer. Since the context lacks this data, I am flagging the use of external information.

This answer relies on standard industry knowledge about AI agent architecture.

### Difference Between Guardrails and Evals for AI Agents

**1. Guardrails**
*   **Definition:** Guardrails are real-time safety mechanisms applied during execution. They act as filters or constraints to stop the agent from doing harmful or unauthorized things.
*   **Function:** They run in the "hot path." Examples include input sanitization, output filtering, permission checks before tool use, and rate limiting.
*   **Goal:** Keep the agent safe and compliant while it works.

**2. Evals (Evaluations)**
*   **Definition:** Evals are testing processes applied during development or after deployment to measure quality and performance.
*   **Function:** They run offline or in development. Examples include benchmarking against test data, measuring latency, checking hallucination rates, and scoring relevance.
*   **Goal:** Measure performance, find regressions, and guide improvements.

### When to Use Each

*   **Use Guardrails when:**
    *   You need to stop immediate harm in production, like preventing an agent from deleting a database.
    *   You must enforce security policies in real-time.
    *   You want to constrain behavior to a specific scope during live interactions.

*   **Use Evals when:**
    *   You are developing an agent and need to measure performance against a baseline.
    *   You want to compare model versions or prompt strategies.
    *   You need to quantify accuracy, latency, or cost for stakeholders.
    *   You are debugging underperformance by analyzing failure cases.

### Summary
*   **Guardrails** = **Prevention** (Real-time safety controls).
*   **Evals** = **Measurement** (Quality assessment).

Evals help you build a good agent. Guardrails ensure it doesn't break things in production.