ishandutta2007 Eval-Driven Development
Overview
Eval-Driven Development ensures that AI features behave deterministically and predictably by testing them against a golden dataset using automated evaluators.
When to Use
- Building an AI-powered feature
- Tuning prompts or changing underlying models
- Implementing RAG pipelines
Process
- Curate Golden Dataset: Create diverse test cases including edge cases.
- Define Metrics: Choose appropriate evaluators (e.g., exact match, semantic similarity, LLM-as-a-judge).
- Run Pipeline: Execute the AI feature over the dataset and collect results.
- Analyze Failures: Inspect low-scoring examples and update prompts or logic.
- Establish Baseline: Set a minimum threshold for CI/CD checks.
Common Rationalizations
| Rationalization | Why It Is Wrong |
|---|---|
| "Manual spot checks are enough." | Spot checks miss regressions across prompts, model versions, and edge cases. |
| "We can add evals after launch." | Without a baseline, you cannot tell whether a later prompt or model change improved behavior. |
| "The judge model says it is good." | LLM judges need criteria, calibration examples, and failure review before they are trustworthy. |
Red Flags
- No golden dataset exists
- Metrics are vague or not tied to user-visible quality
- Low-scoring examples are ignored instead of inspected
- The baseline threshold is chosen after seeing the desired result
Verification
Before finishing, confirm:
- The golden dataset includes normal, edge, and known-failure cases
- Metrics and evaluator prompts are committed or otherwise reproducible
- The current model/prompt has a recorded baseline
- Failure examples have been reviewed and categorized