> ## Documentation Index
> Fetch the complete documentation index at: https://openrouter-d02e98a0-mintlify-5b6e02fd.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Caching - Go SDK

> Caching type definition

<Warning>
  The Go SDK and docs are currently in beta.
  Report issues on [GitHub](https://github.com/OpenRouterTeam/go-sdk/issues).
</Warning>

Enable automatic prompt caching. When set at the top level, the system automatically applies cache breakpoints to the last cacheable block in the request. Currently supported for Anthropic Claude models.

## Fields

| Field  | Type                                                                                                   | Required             | Description | Example |
| ------ | ------------------------------------------------------------------------------------------------------ | -------------------- | ----------- | ------- |
| `TTL`  | [\*components.AnthropicCacheControlTTL](/client-sdks/go/api-reference/models/anthropiccachecontrolttl) | :heavy\_minus\_sign: | N/A         | 5m      |
| `Type` | [components.ToolTypeEphemeral](/client-sdks/go/api-reference/models/tooltypeephemeral)                 | :heavy\_check\_mark: | N/A         |         |