If you look at the schema for the PolicyResource's evaluate action, it returns an array of objects containing resource, actions, attributes and advices. However, the generated SDK PoliciesOperations#evaluate(EvaluateRequest) method returns a single EvaluateResponse object, which has those items itself. The method signature should instead be List<EvaluateResponse> evaluate(EvaluateRequest request). This issue would also affect any request schemas that are an array at the top level.
Look at the SDK class structures.