> ## Documentation Index
> Fetch the complete documentation index at: https://wb-21fd5541-docs-1778-mysql-updates.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Class: EvaluationLogger

> TypeScript SDK reference

[weave](../) / EvaluationLogger

EvaluationLogger enables incremental logging of predictions and scores.

Unlike the traditional Evaluation class which requires upfront dataset and batch processing,
EvaluationLogger allows you to log predictions as they happen, with flexible scoring.

`Example`

```ts theme={null}
const ev = new EvaluationLogger({name: 'my-eval', dataset: 'my-dataset'});

for (const example of streamingData) {
  const output = await myModel.predict(example);
  const pred = await ev.logPrediction(example, output);

  if (shouldScore(output)) {
    await pred.logScore("accuracy", calculateAccuracy(output));
  }
  await pred.finish();
}

await ev.logSummary();
```

## Table of contents

### Constructors

* [constructor](./EvaluationLogger#constructor)

### Methods

* [logPrediction](./EvaluationLogger#logprediction)
* [logSummary](./EvaluationLogger#logsummary)

## Constructors

### constructor

• **new EvaluationLogger**(`options`): [`EvaluationLogger`](./EvaluationLogger)

#### Parameters

| Name      | Type                      |
| :-------- | :------------------------ |
| `options` | `EvaluationLoggerOptions` |

#### Returns

[`EvaluationLogger`](./EvaluationLogger)

#### Defined in

[evaluationLogger.ts:502](https://github.com/wandb/weave/blob/5d9590d2658eeb69c9c9f04342e107bf9a0a4c90/sdks/node/src/evaluationLogger.ts#L502)

## Methods

### logPrediction

▸ **logPrediction**(`inputs`, `output`): `Promise`\<[`ScoreLogger`](./ScoreLogger)>

Log a prediction with its input and output.
Creates a predict\_and\_score call (with child predict call).
Returns a ScoreLogger for adding scores.

#### Parameters

| Name     | Type                       |
| :------- | :------------------------- |
| `inputs` | `Record`\<`string`, `any`> |
| `output` | `any`                      |

#### Returns

`Promise`\<[`ScoreLogger`](./ScoreLogger)>

#### Defined in

[evaluationLogger.ts:579](https://github.com/wandb/weave/blob/5d9590d2658eeb69c9c9f04342e107bf9a0a4c90/sdks/node/src/evaluationLogger.ts#L579)

***

### logSummary

▸ **logSummary**(`summary?`): `Promise`\<`void`>

Log a summary and finalize the evaluation.
Creates a summarize call and finishes the evaluate call.

#### Parameters

| Name       | Type                       |
| :--------- | :------------------------- |
| `summary?` | `Record`\<`string`, `any`> |

#### Returns

`Promise`\<`void`>

#### Defined in

[evaluationLogger.ts:669](https://github.com/wandb/weave/blob/5d9590d2658eeb69c9c9f04342e107bf9a0a4c90/sdks/node/src/evaluationLogger.ts#L669)