Lesson 1964 of 2116
Building a Lightweight Eval Harness
Score model outputs against fixed cases on every change.
Lesson map
What this lesson covers
Learning path
The main moves in order
- 1The premise
- 2eval
- 3harness
- 4metrics
Concept cluster
Terms to connect while reading
Section 1
The premise
You don't need a heavy framework. A folder of test cases and a small runner gets you 80% of the value.
What AI does well here
- Run a fixed set of cases and emit pass/fail with diffs.
- Compare two model versions on the same suite.
What AI cannot do
- Tell you which metric matters for your product.
- Capture quality dimensions you never measured.
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