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

# Turn

> TypeScript SDK reference

Defined in: [src/genai/turn.ts:92](https://github.com/wandb/weave/blob/8c5f077eb11c42b84000726ff20504abc728d3fb/sdks/node/src/genai/turn.ts#L92)

## Extends

* `SpanBase`

## Accessors

### agentName

#### Get Signature

> **get** **agentName**(): `string`

Defined in: [src/genai/turn.ts:103](https://github.com/wandb/weave/blob/8c5f077eb11c42b84000726ff20504abc728d3fb/sdks/node/src/genai/turn.ts#L103)

##### Returns

`string`

***

### model

#### Get Signature

> **get** **model**(): `string`

Defined in: [src/genai/turn.ts:107](https://github.com/wandb/weave/blob/8c5f077eb11c42b84000726ff20504abc728d3fb/sdks/node/src/genai/turn.ts#L107)

##### Returns

`string`

## Methods

### ~~addEvent()~~

<Warning>
  **Deprecated.** Record this data via [setAttributes](#setattributes) instead.
  OpenTelemetry is phasing out the Span Event API (`Span.addEvent`). This
  method still works and existing span-event data stays valid.
  See [https://opentelemetry.io/blog/2026/deprecating-span-events/](https://opentelemetry.io/blog/2026/deprecating-span-events/)
</Warning>

> **addEvent**(`name`, `attributes?`, `startTime?`): `this`

Defined in: [src/genai/spanBase.ts:82](https://github.com/wandb/weave/blob/8c5f077eb11c42b84000726ff20504abc728d3fb/sdks/node/src/genai/spanBase.ts#L82)

Add a named event to the span. Useful for marking non-span moments such as
context compaction, tool-loop detection, or guardrail trips. Warns and
no-ops after `end()`. Mirrors OTel `Span.addEvent`.

#### Parameters

##### name

`string`

##### attributes?

`Attributes`

##### startTime?

`TimeInput`

#### Returns

`this`

#### Example

```ts twoslash theme={null}
// @noErrors
span.addEvent('context_compacted', {removedMessages: 12});
```

#### Inherited from

`SpanBase.addEvent`

***

### end()

> **end**(`opts?`): `void`

Defined in: [src/genai/turn.ts:241](https://github.com/wandb/weave/blob/8c5f077eb11c42b84000726ff20504abc728d3fb/sdks/node/src/genai/turn.ts#L241)

Read current field values (to reflect mutations made via `record()`
since `start`) and close the span. Idempotent. Pass `error` to mark
it as failed; pass `endTime` to backdate the close.

#### Parameters

##### opts?

`SpanEndOptions`

#### Returns

`void`

***

### record()

> **record**(`opts`): `this`

Defined in: [src/genai/turn.ts:201](https://github.com/wandb/weave/blob/8c5f077eb11c42b84000726ff20504abc728d3fb/sdks/node/src/genai/turn.ts#L201)

Bulk-set any subset of the mutable fields. Replaces (does not merge).
Useful for assigning everything at once after a provider call returns.

#### Parameters

##### opts

###### agentDescription?

`string`

###### agentId?

`string`

###### agentName?

`string`

###### agentVersion?

`string`

###### messages?

[`Message`](./message)\[]

###### model?

`string`

###### systemInstructions?

`string`\[]

#### Returns

`this`

***

### ~~setAttribute()~~

<Warning>
  **Deprecated.** Use [setAttributes](#setattributes) instead, which mirrors the Python
  SDK's `set_attributes` and OTel's `Span.setAttributes`. Retained as a thin
  alias so existing single-attribute callers keep working. Only `Turn`
  carries this — the other emitters never shipped a singular form.
</Warning>

> **setAttribute**(`key`, `value`): `this`

Defined in: [src/genai/turn.ts:193](https://github.com/wandb/weave/blob/8c5f077eb11c42b84000726ff20504abc728d3fb/sdks/node/src/genai/turn.ts#L193)

#### Parameters

##### key

`string`

##### value

`AttributeValue`

#### Returns

`this`

***

### setAttributes()

> **setAttributes**(`attributes`): `this`

Defined in: [src/genai/spanBase.ts:63](https://github.com/wandb/weave/blob/8c5f077eb11c42b84000726ff20504abc728d3fb/sdks/node/src/genai/spanBase.ts#L63)

Set multiple attributes on the span at once. Warns and no-ops after
`end()`. Mirrors OTel `Span.setAttributes` (and the Python SDK's
`set_attributes`).

#### Parameters

##### attributes

`Attributes`

#### Returns

`this`

#### Example

```ts twoslash theme={null}
// @noErrors
span.setAttributes({'weave.tag': 'prod', 'gen_ai.response.id': id});
```

#### Inherited from

`SpanBase.setAttributes`

***

### startLLM()

> **startLLM**(`opts`): [`LLM`](./llm)

Defined in: [src/genai/turn.ts:161](https://github.com/wandb/weave/blob/8c5f077eb11c42b84000726ff20504abc728d3fb/sdks/node/src/genai/turn.ts#L161)

Start a child LLM span under this Turn.

#### Parameters

##### opts

[`LLMInit`](./llminit)

#### Returns

[`LLM`](./llm)

***

### startSubagent()

> **startSubagent**(`opts`): [`SubAgent`](./subagent)

Defined in: [src/genai/turn.ts:179](https://github.com/wandb/weave/blob/8c5f077eb11c42b84000726ff20504abc728d3fb/sdks/node/src/genai/turn.ts#L179)

Start a child SubAgent span under this Turn.

#### Parameters

##### opts

[`SubAgentInit`](./subagentinit)

#### Returns

[`SubAgent`](./subagent)

***

### startTool()

> **startTool**(`opts`): [`Tool`](./tool)

Defined in: [src/genai/turn.ts:170](https://github.com/wandb/weave/blob/8c5f077eb11c42b84000726ff20504abc728d3fb/sdks/node/src/genai/turn.ts#L170)

Start a child Tool span under this Turn.

#### Parameters

##### opts

[`ToolInit`](./toolinit)

#### Returns

[`Tool`](./tool)