---
title: metadata
framework: foundationmodels
role: symbol
role_heading: Instance Property
path: foundationmodels/languagemodelsession/usage-swift.struct/metadata
---

# metadata

Language models that provide other kinds of usage statistics may encode them in metadata.

## Declaration

```swift
var metadata: [String : any Sendable & Codable & Equatable]
```

## See Also

### Updating the usage

- [input](foundationmodels/languagemodelsession/usage-swift.struct/input-swift.property.md)
- [LanguageModelSession.Usage.Input](foundationmodels/languagemodelsession/usage-swift.struct/input-swift.struct.md)
- [output](foundationmodels/languagemodelsession/usage-swift.struct/output-swift.property.md)
- [LanguageModelSession.Usage.Output](foundationmodels/languagemodelsession/usage-swift.struct/output-swift.struct.md)
- [totalTokenCount](foundationmodels/languagemodelsession/usage-swift.struct/totaltokencount.md)