# tinker_cookbook.eval.TrainingClientEvaluator

## *class* [**tinker_cookbook.eval.TrainingClientEvaluator**](https://github.com/thinking-machines-lab/tinker-cookbook/blob/main/tinker_cookbook/eval/evaluators.py#L12)()

An evaluator that uses a TrainingClient to compute metrics (e.g., loss).

```python
class NLLEval(TrainingClientEvaluator):
async def __call__(self, training_client):
loss = await compute_nll(training_client, self.eval_data)
return {"eval/nll": loss}
```

### [**__call__**](https://github.com/thinking-machines-lab/tinker-cookbook/blob/main/tinker_cookbook/eval/evaluators.py#L23)(*training_client*)

Run evaluation and return a dict of metric names to values.

**Parameters:**

- [**training_client**](https://github.com/thinking-machines-lab/tinker-cookbook/blob/main/tinker_cookbook/eval/evaluators.py#L23) (*tinker.[TrainingClient](https://tinker-docs.thinkingmachines.ai/tinker/api-reference/trainingclient/index.md)*) – The Tinker training client to evaluate with.

**Returns:** A dict mapping metric names to float values.