📄 ai-sdk/docs/troubleshooting/model-is-not-assignable-to-type

File: model-is-not-assignable-to-type.md | Updated: 11/15/2025

Source: https://ai-sdk.dev/docs/troubleshooting/model-is-not-assignable-to-type

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Copy markdown

Model is not assignable to type "LanguageModelV1"

=============================================================================================================================================================================

Issue


I have updated the AI SDK and now I get the following error: Type 'SomeModel' is not assignable to type 'LanguageModelV1'.

Similar errors can occur with EmbeddingModelV2 as well.

Background


Sometimes new features are being added to the model specification. This can cause incompatibilities with older provider versions.

Solution


Update your provider packages and the AI SDK to the latest version.

On this page

Model is not assignable to type "LanguageModelV1"

Issue

Background

Solution

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