Lesson 2069 of 2116
Evals: How You Actually Know if Your AI Feature Works
Without evals you are vibes-driven. With evals you can ship.
Lesson map
What this lesson covers
Learning path
The main moves in order
- 1The premise
- 2evals
- 3test sets
- 4regression testing
Concept cluster
Terms to connect while reading
Section 1
The premise
Evals are the unit tests of AI development: a curated set of inputs with expected behaviors, run automatically against every change. Teams without evals are guessing.
What AI does well here
- Catching regressions when prompts, models, or data change
- Comparing model versions, providers, or fine-tunes objectively
- Measuring user-impacting metrics, not just generic benchmarks
- Building intuition over time about where the system fails
What AI cannot do
- Replace human review on subjective outputs entirely
- Eliminate the need to update the eval set as the product evolves
- Be created perfectly the first time — they evolve with the product
Key terms in this lesson
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