diff --git a/tests/baselines/reference/api/tsserverlibrary.d.ts b/tests/baselines/reference/api/tsserverlibrary.d.ts
index 55d0fe287b3..b764b02980e 100644
--- a/tests/baselines/reference/api/tsserverlibrary.d.ts
+++ b/tests/baselines/reference/api/tsserverlibrary.d.ts
@@ -720,7 +720,7 @@ declare namespace ts {
         readonly kind: SyntaxKind.Parameter;
         readonly parent: SignatureDeclaration;
         readonly dotDotDotToken?: DotDotDotToken;
-        readonly name: BindingName;
+        readonly name?: BindingName;
         readonly questionToken?: QuestionToken;
         readonly type?: TypeNode;
         readonly initializer?: Expression;
@@ -3355,8 +3355,8 @@ declare namespace ts {
         updateComputedPropertyName(node: ComputedPropertyName, expression: Expression): ComputedPropertyName;
         createTypeParameterDeclaration(name: string | Identifier, constraint?: TypeNode, defaultType?: TypeNode): TypeParameterDeclaration;
         updateTypeParameterDeclaration(node: TypeParameterDeclaration, name: Identifier, constraint: TypeNode | undefined, defaultType: TypeNode | undefined): TypeParameterDeclaration;
-        createParameterDeclaration(decorators: readonly Decorator[] | undefined, modifiers: readonly Modifier[] | undefined, dotDotDotToken: DotDotDotToken | undefined, name: string | BindingName, questionToken?: QuestionToken, type?: TypeNode, initializer?: Expression): ParameterDeclaration;
-        updateParameterDeclaration(node: ParameterDeclaration, decorators: readonly Decorator[] | undefined, modifiers: readonly Modifier[] | undefined, dotDotDotToken: DotDotDotToken | undefined, name: string | BindingName, questionToken: QuestionToken | undefined, type: TypeNode | undefined, initializer: Expression | undefined): ParameterDeclaration;
+        createParameterDeclaration(decorators: readonly Decorator[] | undefined, modifiers: readonly Modifier[] | undefined, dotDotDotToken: DotDotDotToken | undefined, name: string | BindingName | undefined, questionToken?: QuestionToken, type?: TypeNode, initializer?: Expression): ParameterDeclaration;
+        updateParameterDeclaration(node: ParameterDeclaration, decorators: readonly Decorator[] | undefined, modifiers: readonly Modifier[] | undefined, dotDotDotToken: DotDotDotToken | undefined, name: string | BindingName | undefined, questionToken: QuestionToken | undefined, type: TypeNode | undefined, initializer: Expression | undefined): ParameterDeclaration;
         createDecorator(expression: Expression): Decorator;
         updateDecorator(node: Decorator, expression: Expression): Decorator;
         createPropertySignature(modifiers: readonly Modifier[] | undefined, name: PropertyName | string, questionToken: QuestionToken | undefined, type: TypeNode | undefined): PropertySignature;
@@ -10693,9 +10693,9 @@ declare namespace ts {
     /** @deprecated Use `factory.updateTypeParameterDeclaration` or the factory supplied by your transformation context instead. */
     const updateTypeParameterDeclaration: (node: TypeParameterDeclaration, name: Identifier, constraint: TypeNode | undefined, defaultType: TypeNode | undefined) => TypeParameterDeclaration;
     /** @deprecated Use `factory.createParameterDeclaration` or the factory supplied by your transformation context instead. */
-    const createParameter: (decorators: readonly Decorator[] | undefined, modifiers: readonly Modifier[] | undefined, dotDotDotToken: DotDotDotToken | undefined, name: string | BindingName, questionToken?: QuestionToken | undefined, type?: TypeNode | undefined, initializer?: Expression | undefined) => ParameterDeclaration;
+    const createParameter: (decorators: readonly Decorator[] | undefined, modifiers: readonly Modifier[] | undefined, dotDotDotToken: DotDotDotToken | undefined, name: string | BindingName | undefined, questionToken?: QuestionToken | undefined, type?: TypeNode | undefined, initializer?: Expression | undefined) => ParameterDeclaration;
     /** @deprecated Use `factory.updateParameterDeclaration` or the factory supplied by your transformation context instead. */
-    const updateParameter: (node: ParameterDeclaration, decorators: readonly Decorator[] | undefined, modifiers: readonly Modifier[] | undefined, dotDotDotToken: DotDotDotToken | undefined, name: string | BindingName, questionToken: QuestionToken | undefined, type: TypeNode | undefined, initializer: Expression | undefined) => ParameterDeclaration;
+    const updateParameter: (node: ParameterDeclaration, decorators: readonly Decorator[] | undefined, modifiers: readonly Modifier[] | undefined, dotDotDotToken: DotDotDotToken | undefined, name: string | BindingName | undefined, questionToken: QuestionToken | undefined, type: TypeNode | undefined, initializer: Expression | undefined) => ParameterDeclaration;
     /** @deprecated Use `factory.createDecorator` or the factory supplied by your transformation context instead. */
     const createDecorator: (expression: Expression) => Decorator;
     /** @deprecated Use `factory.updateDecorator` or the factory supplied by your transformation context instead. */
diff --git a/tests/baselines/reference/api/typescript.d.ts b/tests/baselines/reference/api/typescript.d.ts
index 0c176320553..4ea60057110 100644
--- a/tests/baselines/reference/api/typescript.d.ts
+++ b/tests/baselines/reference/api/typescript.d.ts
@@ -720,7 +720,7 @@ declare namespace ts {
         readonly kind: SyntaxKind.Parameter;
         readonly parent: SignatureDeclaration;
         readonly dotDotDotToken?: DotDotDotToken;
-        readonly name: BindingName;
+        readonly name?: BindingName;
         readonly questionToken?: QuestionToken;
         readonly type?: TypeNode;
         readonly initializer?: Expression;
@@ -3355,8 +3355,8 @@ declare namespace ts {
         updateComputedPropertyName(node: ComputedPropertyName, expression: Expression): ComputedPropertyName;
         createTypeParameterDeclaration(name: string | Identifier, constraint?: TypeNode, defaultType?: TypeNode): TypeParameterDeclaration;
         updateTypeParameterDeclaration(node: TypeParameterDeclaration, name: Identifier, constraint: TypeNode | undefined, defaultType: TypeNode | undefined): TypeParameterDeclaration;
-        createParameterDeclaration(decorators: readonly Decorator[] | undefined, modifiers: readonly Modifier[] | undefined, dotDotDotToken: DotDotDotToken | undefined, name: string | BindingName, questionToken?: QuestionToken, type?: TypeNode, initializer?: Expression): ParameterDeclaration;
-        updateParameterDeclaration(node: ParameterDeclaration, decorators: readonly Decorator[] | undefined, modifiers: readonly Modifier[] | undefined, dotDotDotToken: DotDotDotToken | undefined, name: string | BindingName, questionToken: QuestionToken | undefined, type: TypeNode | undefined, initializer: Expression | undefined): ParameterDeclaration;
+        createParameterDeclaration(decorators: readonly Decorator[] | undefined, modifiers: readonly Modifier[] | undefined, dotDotDotToken: DotDotDotToken | undefined, name: string | BindingName | undefined, questionToken?: QuestionToken, type?: TypeNode, initializer?: Expression): ParameterDeclaration;
+        updateParameterDeclaration(node: ParameterDeclaration, decorators: readonly Decorator[] | undefined, modifiers: readonly Modifier[] | undefined, dotDotDotToken: DotDotDotToken | undefined, name: string | BindingName | undefined, questionToken: QuestionToken | undefined, type: TypeNode | undefined, initializer: Expression | undefined): ParameterDeclaration;
         createDecorator(expression: Expression): Decorator;
         updateDecorator(node: Decorator, expression: Expression): Decorator;
         createPropertySignature(modifiers: readonly Modifier[] | undefined, name: PropertyName | string, questionToken: QuestionToken | undefined, type: TypeNode | undefined): PropertySignature;
@@ -6882,9 +6882,9 @@ declare namespace ts {
     /** @deprecated Use `factory.updateTypeParameterDeclaration` or the factory supplied by your transformation context instead. */
     const updateTypeParameterDeclaration: (node: TypeParameterDeclaration, name: Identifier, constraint: TypeNode | undefined, defaultType: TypeNode | undefined) => TypeParameterDeclaration;
     /** @deprecated Use `factory.createParameterDeclaration` or the factory supplied by your transformation context instead. */
-    const createParameter: (decorators: readonly Decorator[] | undefined, modifiers: readonly Modifier[] | undefined, dotDotDotToken: DotDotDotToken | undefined, name: string | BindingName, questionToken?: QuestionToken | undefined, type?: TypeNode | undefined, initializer?: Expression | undefined) => ParameterDeclaration;
+    const createParameter: (decorators: readonly Decorator[] | undefined, modifiers: readonly Modifier[] | undefined, dotDotDotToken: DotDotDotToken | undefined, name: string | BindingName | undefined, questionToken?: QuestionToken | undefined, type?: TypeNode | undefined, initializer?: Expression | undefined) => ParameterDeclaration;
     /** @deprecated Use `factory.updateParameterDeclaration` or the factory supplied by your transformation context instead. */
-    const updateParameter: (node: ParameterDeclaration, decorators: readonly Decorator[] | undefined, modifiers: readonly Modifier[] | undefined, dotDotDotToken: DotDotDotToken | undefined, name: string | BindingName, questionToken: QuestionToken | undefined, type: TypeNode | undefined, initializer: Expression | undefined) => ParameterDeclaration;
+    const updateParameter: (node: ParameterDeclaration, decorators: readonly Decorator[] | undefined, modifiers: readonly Modifier[] | undefined, dotDotDotToken: DotDotDotToken | undefined, name: string | BindingName | undefined, questionToken: QuestionToken | undefined, type: TypeNode | undefined, initializer: Expression | undefined) => ParameterDeclaration;
     /** @deprecated Use `factory.createDecorator` or the factory supplied by your transformation context instead. */
     const createDecorator: (expression: Expression) => Decorator;
     /** @deprecated Use `factory.updateDecorator` or the factory supplied by your transformation context instead. */