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# LanguageModelSession.Error

A failure caused by incorrect use of a language model session.

```
enum Error
```

## Topics

### Getting the session errors

[`case concurrentRequests`](/documentation/FoundationModels/LanguageModelSession/Error/concurrentRequests)

The session received multiple concurrent requests.

[`case transcriptMutationWhileResponding`](/documentation/FoundationModels/LanguageModelSession/Error/transcriptMutationWhileResponding)

A request mutated the session’s transcript while it was in progress.

## Relationships

### Conforms To

[`Hashable`](/documentation/Swift/Hashable)

[`LocalizedError`](/documentation/Foundation/LocalizedError)

[`Equatable`](/documentation/Swift/Equatable)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`Error`](/documentation/Swift/Error)

[`Escapable`](/documentation/Swift/Escapable)

[`Copyable`](/documentation/Swift/Copyable)

[`CustomDebugStringConvertible`](/documentation/Swift/CustomDebugStringConvertible)

[`Sendable`](/documentation/Swift/Sendable)

---

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