> ## Documentation Index
> Fetch the complete documentation index at: https://docs.galileo.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# LlmMetrics

***

# Class: LlmMetrics

Defined in: [src/types/logging/span.types.ts](https://github.com/rungalileo/galileo-js/blob/main/src/types/logging/span.types.ts)

## Extends

* [`Metrics`](/sdk-api/typescript/reference/types/classes/Metrics)

## Indexable

```ts theme={null}
[key: string]:
  | undefined
  | MetricValueType
| () => Record<string, MetricValueType | undefined>
```

## Constructors

### Constructor

```ts theme={null}
new LlmMetrics(options: LlmMetricsOptions): LlmMetrics;
```

Defined in: [src/types/logging/span.types.ts](https://github.com/rungalileo/galileo-js/blob/main/src/types/logging/span.types.ts)

#### Parameters

##### options

[`LlmMetricsOptions`](/sdk-api/typescript/reference/types/interfaces/LlmMetricsOptions)

#### Returns

`LlmMetrics`

#### Overrides

[`Metrics`](/sdk-api/typescript/reference/types/classes/Metrics).[`constructor`](/sdk-api/typescript/reference/types/classes/Metrics.mdx#constructor)

## Properties

### durationNs?

```ts theme={null}
optional durationNs: number;
```

Defined in: [src/types/logging/step.types.ts](https://github.com/rungalileo/galileo-js/blob/main/src/types/logging/step.types.ts)

#### Inherited from

[`Metrics`](/sdk-api/typescript/reference/types/classes/Metrics).[`durationNs`](/sdk-api/typescript/reference/types/classes/Metrics.mdx#durationns)

***

### numInputTokens?

```ts theme={null}
optional numInputTokens: number;
```

Defined in: [src/types/logging/span.types.ts](https://github.com/rungalileo/galileo-js/blob/main/src/types/logging/span.types.ts)

***

### numOutputTokens?

```ts theme={null}
optional numOutputTokens: number;
```

Defined in: [src/types/logging/span.types.ts](https://github.com/rungalileo/galileo-js/blob/main/src/types/logging/span.types.ts)

***

### numTotalTokens?

```ts theme={null}
optional numTotalTokens: number;
```

Defined in: [src/types/logging/span.types.ts](https://github.com/rungalileo/galileo-js/blob/main/src/types/logging/span.types.ts)

***

### timeToFirstTokenNs?

```ts theme={null}
optional timeToFirstTokenNs: number;
```

Defined in: [src/types/logging/span.types.ts](https://github.com/rungalileo/galileo-js/blob/main/src/types/logging/span.types.ts)

## Methods

### toJSON()

```ts theme={null}
toJSON(): Record<string, MetricValueType | undefined>;
```

Defined in: [src/types/logging/span.types.ts](https://github.com/rungalileo/galileo-js/blob/main/src/types/logging/span.types.ts)

#### Returns

`Record`\<`string`, [`MetricValueType`](/sdk-api/typescript/reference/types/type-aliases/MetricValueType) | `undefined`>

#### Overrides

[`Metrics`](/sdk-api/typescript/reference/types/classes/Metrics).[`toJSON`](/sdk-api/typescript/reference/types/classes/Metrics.mdx#tojson)