LLM Evaluation Pipeline Guide for Product Teams
·11 min read
If you cannot measure quality repeatedly, you cannot ship AI safely. A good evaluation pipeline turns subjective model behavior into objective release criteria.
Core components
- Dataset: representative tasks and edge cases.
- Judging: deterministic checks + rubric scoring.
- Metrics: success, safety, latency, and cost.
- Baseline comparison: current production vs candidate.
Dataset structure
{
"id": "support-refund-001",
"input": "User asks for refund after 40 days",
"context": "...",
"expected": "Policy-compliant refusal with alternatives",
"tags": ["support", "policy", "high-risk"]
}Recommended metric set
| Metric | Type | Why it matters |
|---|---|---|
| Task success | Quality | Measures usefulness for end users |
| Factual error rate | Safety | Controls hallucinations |
| Policy violation rate | Safety | Prevents harmful responses |
| P95 latency | Performance | Protects UX |
| Cost / 1k requests | Business | Protects margins |
Scoring pattern
final_score = 0.50 * task_success - 0.25 * factual_error_rate - 0.15 * policy_violation_rate - 0.10 * latency_penalty
Regression detection
- Always run candidate and baseline on the same dataset snapshot.
- Flag per-intent degradation, not just aggregate score drops.
- Set hard blocks for high-risk scenarios (payments, compliance, legal).
Automation flow
on pull_request: - run quick eval suite (critical intents) on main merge: - run full eval suite - publish scorecard artifact - open approval gate if delta below threshold
Common mistakes
- Using only easy prompts in evaluation sets.
- Over-relying on one LLM judge without deterministic checks.
- Ignoring cost regression while optimizing quality.
- Not versioning datasets, making comparisons invalid.
Takeaway
Your eval pipeline should answer one operational question: Is this candidate safer and better than production within budget? If it cannot, improve the pipeline before scaling traffic.