> For the complete documentation index, see [llms.txt](https://docs.layerlens.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.layerlens.ai/more-in-this-section-6/score-reasoning.md).

# Recipe: Score reasoning chains

Recipe — score reasoning chains with chain-of-thought aware judges.

**When to use:** model exposes its reasoning trace; you need the trace to be valid not just the final answer.

## Steps

1. Capture chain-of-thought as a span (`kind: chain`).
2. Build judge that scores both final answer + reasoning soundness.
3. Penalize reasoning errors that happen to land on a correct answer.

## Code

```python
judge = client.judges.create(
 name="reasoning-soundness",
 evaluation_goal="Rate (1) final-answer correctness and (2) reasoning soundness. Penalize correct answers that arrived via flawed reasoning."
)
```

## See also

* [Concept: Traces and spans](/6.-build-wire-your-code/traces-and-spans.md)
* [Concept: Judges](/8.-evaluate-score-the-outputs/judges-1.md)