```ts
type GuardImageFormat = "png" | "jpeg";
```

Defined in: [src/types/messages.ts:829](https://github.com/strands-agents/harness-sdk/blob/c3b403c7c41f9fe7b7e704bb8f8d2e6698d3b97e/strands-ts/src/types/messages.ts#L829)

Image format for guard content. Only formats supported by Bedrock guardrails.