         }
     }
 
-    // MARK: - Positive Tests
+    // MARK: - Classifiers CRUD
 
     /** Retrieve a list of user-trained classifiers. */
     func testListClassifiers() {

        waitForExpectations(timeout: 60)
    }

    /** Detect faces by URL. */
    func testDetectFacesByURL() {
        let expectation = self.expectation(description: "Detect faces by URL.")

            }
        }
    }

    /** Get the Core ML model for a trained classifier. */
    func testGetCoreMlModel() {
        let expectation = self.expectation(description: "Get the Core ML model for a trained classifier.")
        visualRecognition.getCoreMlModel(classifierID: classifierID, failure: failWithError) {
            coreMLModel in
            XCTAssertNotNil(coreMLModel)
            expectation.fulfill()
        }
        waitForExpectations()
    }

    // MARK: - Classify

    /** Classify an image by URL using the default classifier and all default parameters. */
    func testClassifyByURL1() {
