What Is Prompt Optimization?
Systematic testing of variations to improve output quality on specific tasks. Without automation, you test one variation at a time. Tools automate: run all variations, score results, show winners.
Key Features
- Golden datasets (test cases + expected outputs)
- Batch testing (run all variations at once)
- Automatic scoring (metrics, LLM-as-Judge)
- Side-by-side comparison UI
- Cost tracking (quality vs. cost trade-offs)
- Multi-model evaluation
- Version control
Tools for Quick A/B Testing
- PromptQuorum: Fast, quorum consensus
- Braintrust: Beautiful comparison UI
- OpenAI Playground: Free, single-model
Tools for Systematic Optimization
- Promptfoo: YAML, git-friendly, open-source
- Braintrust: Golden datasets, A/B testing
- PromptQuorum: Multi-model, detailed metrics
How to Set Up a Golden Dataset
- 1Choose 20—50 representative examples
- 2Document expected output for each
- 3Run current prompt (baseline)
- 4Compare new versions against baseline
- 5Expand quarterly with edge cases
Sources
- OpenAI. Evaluation patterns
- Braintrust. Optimization framework
- Promptfoo. Testing guide
Common Mistakes
- Too-small test set (< 20 examples)
- Overoptimizing for test cases
- Forgetting to version test dataset
- Optimizing for speed instead of quality