• JSONParseError
• InvalidRequestError
• MethodNotFoundError
• InvalidParamsError
• InternalError
• TaskNotFoundError
• TastNotCancelableError
• PushNotificationNotSupportedError
• UnsupportedOperationError
• ContentTypeNotSupportedError
• A2AClientError
• A2AClientHttpError
• A2AClientJSONError
• MissingAPIKeyError

e.g., see https://github.com/google/A2A/blob/main/samples/python/common/types.py#L251