Defined in: [src/models/model.ts:160](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/models/model.ts#L160)

Options for counting tokens in a set of messages.

## Properties

### systemPrompt?

```ts
optional systemPrompt?: SystemPrompt;
```

Defined in: [src/models/model.ts:165](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/models/model.ts#L165)

System prompt to guide the model’s behavior. Can be a simple string or an array of content blocks for advanced caching.

---

### toolSpecs?

```ts
optional toolSpecs?: ToolSpec[];
```

Defined in: [src/models/model.ts:170](https://github.com/strands-agents/harness-sdk/blob/576da59fdc411b55036a7cf66d4e1659a67d4d0d/strands-ts/src/models/model.ts#L170)

Array of tool specifications to include in the count.