diff --git a/packages/context/src/inject.ts b/packages/context/src/inject.ts
index 8631acdc7bd5..9ae4a48cd5cc 100644
--- a/packages/context/src/inject.ts
+++ b/packages/context/src/inject.ts
@@ -107,6 +107,10 @@ export function inject(
       propDecorator(target, propertyKey!);
     } else {
       // It won't happen here as `@inject` is not compatible with ClassDecorator
+      /* istanbul ignore next */
+      throw new Error(
+        '@inject can only be used on a property or a method parameter',
+      );
     }
   };
 }
diff --git a/packages/metadata/src/inspector.ts b/packages/metadata/src/inspector.ts
index f96d51a6a85b..dcc172339530 100644
--- a/packages/metadata/src/inspector.ts
+++ b/packages/metadata/src/inspector.ts
@@ -25,6 +25,8 @@ export class MetadataInspector {
    * Get the metadata associated with the given key for a given class
    * @param key Metadata key
    * @param target Class that contains the metadata
+   * @param ownOnly Optional flag to control if only own metadata is inspected.
+   * The default value is `false` and inherited metadata is inspected.
    */
   static getClassMetadata<T>(
     key: string,
@@ -41,6 +43,8 @@ export class MetadataInspector {
    * target class or prototype
    * @param key Metadata key
    * @param target Class for static methods or prototype for instance methods
+   * @param ownOnly Optional flag to control if only own metadata is inspected.
+   * The default value is `false` and inherited metadata is inspected.
    */
   static getAllMethodMetadata<T>(
     key: string,
@@ -59,6 +63,8 @@ export class MetadataInspector {
    * @param target Class for static methods or prototype for instance methods
    * @param methodName Method name. If not present, default to '' to use
    * the constructor
+   * @param ownOnly Optional flag to control if only own metadata is inspected.
+   * The default value is `false` and inherited metadata is inspected.
    */
   static getMethodMetadata<T>(
     key: string,
@@ -78,6 +84,8 @@ export class MetadataInspector {
    * target class or prototype
    * @param key Metadata key
    * @param target Class for static methods or prototype for instance methods
+   * @param ownOnly Optional flag to control if only own metadata is inspected.
+   * The default value is `false` and inherited metadata is inspected.
    */
   static getAllPropertyMetadata<T>(
     key: string,
@@ -96,6 +104,8 @@ export class MetadataInspector {
    * @param target Class for static properties or prototype for instance
    * properties
    * @param propertyName Property name
+   * @param ownOnly Optional flag to control if only own metadata is inspected.
+   * The default value is `false` and inherited metadata is inspected.
    */
   static getPropertyMetadata<T>(
     key: string,
@@ -116,6 +126,8 @@ export class MetadataInspector {
    * @param target Class for static methods or prototype for instance methods
    * @param methodName Method name. If not present, default to '' to use
    * the constructor
+   * @param ownOnly Optional flag to control if only own metadata is inspected.
+   * The default value is `false` and inherited metadata is inspected.
    */
   static getAllParameterMetadata<T>(
     key: string,
@@ -138,6 +150,8 @@ export class MetadataInspector {
    * @param methodName Method name. If not present, default to '' to use
    * the constructor
    * @param index Index of the parameter, starting with 0
+   * @param ownOnly Optional flag to control if only own metadata is inspected.
+   * The default value is `false` and inherited metadata is inspected.
    */
   static getParameterMetadata<T>(
     key: string,
@@ -155,7 +169,7 @@ export class MetadataInspector {
   }
 
   /**
-   * Get TypeScript design time type for the property
+   * Get TypeScript design time type for a property
    * @param target Class or prototype
    * @param propertyName Property name
    */
@@ -166,6 +180,11 @@ export class MetadataInspector {
     return TSReflector.getMetadata('design:type', target, propertyName);
   }
 
+  /**
+   * Get TypeScript design time type for a method
+   * @param target Class or prototype
+   * @param methodName Method name
+   */
   static getDesignTypeForMethod(
     target: Object,
     methodName: string | symbol,
diff --git a/packages/metadata/test/unit/inspector.test.ts b/packages/metadata/test/unit/inspector.test.ts
index e8fa577b8e08..c5ca61c14eb2 100644
--- a/packages/metadata/test/unit/inspector.test.ts
+++ b/packages/metadata/test/unit/inspector.test.ts
@@ -45,6 +45,51 @@ describe('Inspector for a class', () => {
   });
 });
 
+describe('Inspector for a class for its own metadata', () => {
+  /**
+   * Define `@classDecorator(spec)`
+   * @param spec
+   */
+  function classDecorator(spec: object): ClassDecorator {
+    return ClassDecoratorFactory.createDecorator('test', spec);
+  }
+
+  @classDecorator({x: 1})
+  class BaseController {}
+
+  @classDecorator({y: 2})
+  class SubController extends BaseController {}
+
+  class AnotherController extends BaseController {}
+
+  it('inspects metadata of a base class', () => {
+    const meta = MetadataInspector.getClassMetadata(
+      'test',
+      BaseController,
+      true,
+    );
+    expect(meta).to.eql({x: 1});
+  });
+
+  it('inspects metadata of a sub class', () => {
+    const meta = MetadataInspector.getClassMetadata(
+      'test',
+      SubController,
+      true,
+    );
+    expect(meta).to.eql({x: 1, y: 2});
+  });
+
+  it('inspects metadata of a sub class without override', () => {
+    const meta = MetadataInspector.getClassMetadata(
+      'test',
+      AnotherController,
+      true,
+    );
+    expect(meta).to.be.undefined();
+  });
+});
+
 describe('Inspector for instance properties', () => {
   /**
    * Define `@propertyDecorator(spec)`
@@ -64,6 +109,10 @@ describe('Inspector for instance properties', () => {
     myProp: string;
   }
 
+  class AnotherController extends BaseController {
+    myProp: string;
+  }
+
   it('inspects metadata of all properties of a base class', () => {
     const meta = MetadataInspector.getAllPropertyMetadata(
       'test',
@@ -88,6 +137,23 @@ describe('Inspector for instance properties', () => {
     );
     expect(meta).to.eql({myProp: {x: 1, y: 2}});
   });
+
+  it('inspects own metadata of all properties of a sub class', () => {
+    const meta = MetadataInspector.getAllPropertyMetadata(
+      'test',
+      AnotherController.prototype,
+      true,
+    );
+    expect(meta).to.be.undefined();
+
+    const propertyMeta = MetadataInspector.getPropertyMetadata(
+      'test',
+      AnotherController.prototype,
+      'myProp',
+      true,
+    );
+    expect(propertyMeta).to.be.undefined();
+  });
 });
 
 describe('Inspector for static properties', () => {
@@ -109,6 +175,10 @@ describe('Inspector for static properties', () => {
     static myProp: string;
   }
 
+  class AnotherController extends BaseController {
+    static myProp: string;
+  }
+
   it('inspects metadata of all properties of a base class', () => {
     const meta = MetadataInspector.getAllPropertyMetadata(
       'test',
@@ -133,6 +203,23 @@ describe('Inspector for static properties', () => {
     );
     expect(meta).to.eql({myProp: {x: 1, y: 2}});
   });
+
+  it('inspects own metadata of all properties of a sub class', () => {
+    const meta = MetadataInspector.getAllPropertyMetadata(
+      'test',
+      AnotherController,
+      true,
+    );
+    expect(meta).to.be.undefined();
+
+    const propertyMeta = MetadataInspector.getPropertyMetadata(
+      'test',
+      AnotherController,
+      'myProp',
+      true,
+    );
+    expect(propertyMeta).to.be.undefined();
+  });
 });
 
 describe('Inspector for instance methods', () => {
@@ -154,6 +241,8 @@ describe('Inspector for instance methods', () => {
     myMethod() {}
   }
 
+  class AnotherController extends BaseController {}
+
   it('inspects metadata of all methods of a base class', () => {
     const meta = MetadataInspector.getAllMethodMetadata(
       'test',
@@ -178,6 +267,23 @@ describe('Inspector for instance methods', () => {
     );
     expect(meta).to.eql({myMethod: {x: 1, y: 2}});
   });
+
+  it('inspects own metadata of all methods of a sub class', () => {
+    const meta = MetadataInspector.getAllMethodMetadata(
+      'test',
+      AnotherController.prototype,
+      true,
+    );
+    expect(meta).to.be.undefined();
+
+    const methodMeta = MetadataInspector.getMethodMetadata(
+      'test',
+      AnotherController.prototype,
+      'myMethod',
+      true,
+    );
+    expect(methodMeta).to.be.undefined();
+  });
 });
 
 describe('Inspector for static methods', () => {
@@ -199,6 +305,8 @@ describe('Inspector for static methods', () => {
     static myMethod() {}
   }
 
+  class AnotherController extends BaseController {}
+
   it('inspects metadata of all methods of a base class', () => {
     const meta = MetadataInspector.getAllMethodMetadata('test', BaseController);
     expect(meta).to.eql({myMethod: {x: 1}});
@@ -217,6 +325,29 @@ describe('Inspector for static methods', () => {
     const meta = MetadataInspector.getAllMethodMetadata('test', SubController);
     expect(meta).to.eql({myMethod: {x: 1, y: 2}});
   });
+
+  it('inspects own metadata of all methods of a sub class', () => {
+    const meta = MetadataInspector.getAllMethodMetadata(
+      'test',
+      AnotherController,
+      true,
+    );
+    expect(meta).to.be.undefined();
+
+    const methodMeta = MetadataInspector.getMethodMetadata(
+      'test',
+      AnotherController,
+      'myMethod',
+      true,
+    );
+    expect(methodMeta).to.be.undefined();
+
+    const inherited = MetadataInspector.getAllMethodMetadata(
+      'test',
+      AnotherController,
+    );
+    expect(inherited).to.eql({myMethod: {x: 1}});
+  });
 });
 
 describe('Inspector for parameters of an instance method', () => {
@@ -245,6 +376,8 @@ describe('Inspector for parameters of an instance method', () => {
     ) {}
   }
 
+  class AnotherController extends BaseController {}
+
   it('inspects metadata of all parameters of a method of the base class', () => {
     const meta = MetadataInspector.getAllParameterMetadata(
       'test',
@@ -272,6 +405,31 @@ describe('Inspector for parameters of an instance method', () => {
     );
     expect(meta).to.eql({x: 1, y: 2});
   });
+
+  it('inspects own metadata of all method parameters of a sub class', () => {
+    const meta = MetadataInspector.getAllParameterMetadata(
+      'test',
+      AnotherController.prototype,
+      'myMethod',
+      true,
+    );
+    expect(meta).to.be.undefined();
+
+    const paramsMeta = MetadataInspector.getParameterMetadata(
+      'test',
+      AnotherController.prototype,
+      'myMethod',
+      0,
+      true,
+    );
+    expect(paramsMeta).to.be.undefined();
+
+    const inherited = MetadataInspector.getAllMethodMetadata(
+      'test',
+      AnotherController.prototype,
+    );
+    expect(inherited).to.eql({myMethod: [{x: 1}, undefined]});
+  });
 });
 
 describe('Inspector for parameters of a static method', () => {
@@ -300,6 +458,8 @@ describe('Inspector for parameters of a static method', () => {
     ) {}
   }
 
+  class AnotherController extends BaseController {}
+
   it('inspects metadata of all parameters of a method of the base class', () => {
     const meta = MetadataInspector.getAllParameterMetadata(
       'test',
@@ -327,6 +487,31 @@ describe('Inspector for parameters of a static method', () => {
     );
     expect(meta).to.eql({x: 1, y: 2});
   });
+
+  it('inspects own metadata of all method parameters of a sub class', () => {
+    const meta = MetadataInspector.getAllParameterMetadata(
+      'test',
+      AnotherController,
+      'myMethod',
+      true,
+    );
+    expect(meta).to.be.undefined();
+
+    const paramsMeta = MetadataInspector.getParameterMetadata(
+      'test',
+      AnotherController,
+      'myMethod',
+      0,
+      true,
+    );
+    expect(paramsMeta).to.be.undefined();
+
+    const inherited = MetadataInspector.getAllMethodMetadata(
+      'test',
+      AnotherController,
+    );
+    expect(inherited).to.eql({myMethod: [{x: 1}, undefined]});
+  });
 });
 
 describe('Inspector for parameters of a constructor', () => {