invalid-extension-key

Id

@typespec/openapi/invalid-extension-key

This diagnostic is issued by the @extension decorator when the extension key does not start with x- as required by the OpenAPI v3 specification.

How to fix

Change the extension name to start with x-.

Incorrect

@extension("invalid-name", "value")
model User {
  id: string;
}

Correct

@extension("x-valid-name", "value")
model User {
  id: string;
}