When @standard-schema/spec dependency is missing, the chat function returns any

[eastack]

I followed the Quick Start documentation to create a new project to try out the TanStack AI development experience. However, I noticed that the parameter types of tool function definitions were inferred as unknown, and the return type of the chat function was inferred as any.

To investigate, I cloned the project https://github.com/AlemTuzlak/video-to-social-previews.git and gradually copied its tsconfig.json and package.json into my own project. After restarting VS Code, type inference worked correctly again.

Then I started removing dependencies one by one and restarting VS Code each time. I found that as soon as I removed @standard-schema/spec, type inference broke again. I’m not sure whether there are other contributing factors, but I strongly suspect that this issue is related to the @standard-schema/spec dependency.