AI agents fail in production for a predictable reason: quality is assumed instead of measured.
An evaluation gate makes quality a release requirement. The agent must pass defined tests—under clear thresholds—before changes go live.
What is an evaluation gate?
An evaluation gate is CI for AI behavior. It prevents silent regressions when prompts, tools, models, or knowledge sources change.
What you should evaluate for production agents
1) Output quality
- Correctness (task completion)
- Completeness (required steps included)
- Clarity (usable by downstream systems/users)
2) Grounding and factuality (especially with RAG)
- Uses approved sources
- Avoids invented details
- Provides traceability/citations where applicable
3) Tool safety
- Calls allowed tools only
- Respects approval requirements
- Avoids risky actions when uncertain
4) Operational performance
- Cost per run within budget
- Latency within SLO
- Failure/retry rates within limits
How to build eval gates (practical process)
Step 1: Define success criteria per workflow
Avoid vague goals like “better accuracy.” Define outcomes that can be checked: correct routing, grounded responses, required fields created, approvals enforced.
Step 2: Build a test set that matches reality
Include common cases (60–70%), edge cases (20–30%), and adversarial cases (5–10%) where the agent must refuse or escalate.
Step 3: Choose scoring methods
- Deterministic checks (schema/fields/tool success)
- Rule checks (routing/eligibility logic)
- LLM-as-judge with a clear rubric (for nuanced text)
- Human review sampling for high-risk workflows
Step 4: Set pass/fail thresholds
Align thresholds to risk. Tool safety violations must be zero. Workflow success should meet a defined target on core scenarios. Cost and latency must remain within agreed budgets.
Step 5: Run regressions on every meaningful change
Triggers include prompt/workflow updates, tool schema changes, retrieval/index updates, and model routing changes. If behavior could change, the gate should run.
A simple evaluation gate template
| Area | What you check | Pass condition |
|---|---|---|
| Tool safety | Allowed tools only | 0 violations |
| Approvals | Approvals required for sensitive actions | 100% compliance |
| Grounding | Evidence from approved sources | Meets threshold |
| Workflow success | Correct completion | ≥ target rate |
| Cost | Cost per run | Within budget |
| Latency | End-to-end time | Within SLO |