diff --git a/src/server/client.ts b/src/server/client.ts
index 7a64d9b528c..8203475b06d 100644
--- a/src/server/client.ts
+++ b/src/server/client.ts
@@ -558,8 +558,7 @@ namespace ts.server {
             const request = this.processRequest<protocol.CodeFixRequest>(CommandNames.GetCodeFixes, args);
             const response = this.processResponse<protocol.CodeFixResponse>(request);
 
-            // TODO: GH#20538 shouldn't need cast
-            return (response.body as ReadonlyArray<protocol.CodeFixAction>).map(({ description, changes, fixId }) => ({ description, changes: this.convertChanges(changes, file), fixId }));
+            return response.body.map(({ description, changes, fixId }) => ({ description, changes: this.convertChanges(changes, file), fixId }));
         }
 
         getCombinedCodeFix = notImplemented;
diff --git a/src/server/protocol.ts b/src/server/protocol.ts
index b3cbba27a20..b4ff0aa4037 100644
--- a/src/server/protocol.ts
+++ b/src/server/protocol.ts
@@ -102,8 +102,6 @@ namespace ts.server.protocol {
         GetCodeFixes = "getCodeFixes",
         /* @internal */
         GetCodeFixesFull = "getCodeFixes-full",
-        // TODO: GH#20538
-        /* @internal */
         GetCombinedCodeFix = "getCombinedCodeFix",
         /* @internal */
         GetCombinedCodeFixFull = "getCombinedCodeFix-full",
@@ -557,15 +555,11 @@ namespace ts.server.protocol {
         arguments: CodeFixRequestArgs;
     }
 
-    // TODO: GH#20538
-    /* @internal */
     export interface GetCombinedCodeFixRequest extends Request {
         command: CommandTypes.GetCombinedCodeFix;
         arguments: GetCombinedCodeFixRequestArgs;
     }
 
-    // TODO: GH#20538
-    /* @internal */
     export interface GetCombinedCodeFixResponse extends Response {
         body: CombinedCodeActions;
     }
@@ -622,15 +616,11 @@ namespace ts.server.protocol {
         errorCodes?: ReadonlyArray<number>;
     }
 
-    // TODO: GH#20538
-    /* @internal */
     export interface GetCombinedCodeFixRequestArgs {
         scope: GetCombinedCodeFixScope;
         fixId: {};
     }
 
-    // TODO: GH#20538
-    /* @internal */
     export interface GetCombinedCodeFixScope {
         type: "file";
         args: FileRequestArgs;
@@ -1619,7 +1609,7 @@ namespace ts.server.protocol {
 
     export interface CodeFixResponse extends Response {
         /** The code actions that are available */
-        body?: CodeAction[]; // TODO: GH#20538 CodeFixAction[]
+        body?: CodeFixAction[];
     }
 
     export interface CodeAction {
@@ -1631,15 +1621,11 @@ namespace ts.server.protocol {
         commands?: {}[];
     }
 
-    // TODO: GH#20538
-    /* @internal */
     export interface CombinedCodeActions {
         changes: ReadonlyArray<FileCodeEdits>;
         commands?: ReadonlyArray<{}>;
     }
 
-    // TODO: GH#20538
-    /* @internal */
     export interface CodeFixAction extends CodeAction {
         /**
          * If present, one may call 'getCombinedCodeFix' with this fixId.
diff --git a/src/services/types.ts b/src/services/types.ts
index 597709a7c79..4ebd4a3e76a 100644
--- a/src/services/types.ts
+++ b/src/services/types.ts
@@ -295,10 +295,7 @@ namespace ts {
 
         getSpanOfEnclosingComment(fileName: string, position: number, onlyMultiLine: boolean): TextSpan;
 
-        // TODO: GH#20538 return `ReadonlyArray<CodeFixAction>`
-        getCodeFixesAtPosition(fileName: string, start: number, end: number, errorCodes: ReadonlyArray<number>, formatOptions: FormatCodeSettings): ReadonlyArray<CodeAction>;
-        // TODO: GH#20538
-        /* @internal */
+        getCodeFixesAtPosition(fileName: string, start: number, end: number, errorCodes: ReadonlyArray<number>, formatOptions: FormatCodeSettings): ReadonlyArray<CodeFixAction>;
         getCombinedCodeFix(scope: CombinedCodeFixScope, fixId: {}, formatOptions: FormatCodeSettings): CombinedCodeActions;
         applyCodeActionCommand(action: CodeActionCommand): Promise<ApplyCodeActionCommandResult>;
         applyCodeActionCommand(action: CodeActionCommand[]): Promise<ApplyCodeActionCommandResult[]>;
@@ -327,8 +324,6 @@ namespace ts {
         dispose(): void;
     }
 
-    // TODO: GH#20538
-    /* @internal */
     export interface CombinedCodeFixScope { type: "file"; fileName: string; }
 
     export interface GetCompletionsAtPositionOptions {
@@ -419,8 +414,6 @@ namespace ts {
         commands?: CodeActionCommand[];
     }
 
-    // TODO: GH#20538
-    /* @internal */
     export interface CodeFixAction extends CodeAction {
         /**
          * If present, one may call 'getCombinedCodeFix' with this fixId.
@@ -429,8 +422,6 @@ namespace ts {
         fixId?: {};
     }
 
-    // TODO: GH#20538
-    /* @internal */
     export interface CombinedCodeActions {
         changes: ReadonlyArray<FileTextChanges>;
         commands: ReadonlyArray<CodeActionCommand> | undefined;
diff --git a/tests/baselines/reference/api/tsserverlibrary.d.ts b/tests/baselines/reference/api/tsserverlibrary.d.ts
index a0dfa5f5d17..942ca44a782 100644
--- a/tests/baselines/reference/api/tsserverlibrary.d.ts
+++ b/tests/baselines/reference/api/tsserverlibrary.d.ts
@@ -4091,7 +4091,8 @@ declare namespace ts {
         getDocCommentTemplateAtPosition(fileName: string, position: number): TextInsertion;
         isValidBraceCompletionAtPosition(fileName: string, position: number, openingBrace: number): boolean;
         getSpanOfEnclosingComment(fileName: string, position: number, onlyMultiLine: boolean): TextSpan;
-        getCodeFixesAtPosition(fileName: string, start: number, end: number, errorCodes: ReadonlyArray<number>, formatOptions: FormatCodeSettings): ReadonlyArray<CodeAction>;
+        getCodeFixesAtPosition(fileName: string, start: number, end: number, errorCodes: ReadonlyArray<number>, formatOptions: FormatCodeSettings): ReadonlyArray<CodeFixAction>;
+        getCombinedCodeFix(scope: CombinedCodeFixScope, fixId: {}, formatOptions: FormatCodeSettings): CombinedCodeActions;
         applyCodeActionCommand(action: CodeActionCommand): Promise<ApplyCodeActionCommandResult>;
         applyCodeActionCommand(action: CodeActionCommand[]): Promise<ApplyCodeActionCommandResult[]>;
         applyCodeActionCommand(action: CodeActionCommand | CodeActionCommand[]): Promise<ApplyCodeActionCommandResult | ApplyCodeActionCommandResult[]>;
@@ -4107,6 +4108,10 @@ declare namespace ts {
         getProgram(): Program;
         dispose(): void;
     }
+    interface CombinedCodeFixScope {
+        type: "file";
+        fileName: string;
+    }
     interface GetCompletionsAtPositionOptions {
         includeExternalModuleExports: boolean;
         includeInsertTextCompletions: boolean;
@@ -4184,6 +4189,17 @@ declare namespace ts {
          */
         commands?: CodeActionCommand[];
     }
+    interface CodeFixAction extends CodeAction {
+        /**
+         * If present, one may call 'getCombinedCodeFix' with this fixId.
+         * This may be omitted to indicate that the code fix can't be applied in a group.
+         */
+        fixId?: {};
+    }
+    interface CombinedCodeActions {
+        changes: ReadonlyArray<FileTextChanges>;
+        commands: ReadonlyArray<CodeActionCommand> | undefined;
+    }
     type CodeActionCommand = InstallPackageAction;
     interface InstallPackageAction {
     }
@@ -5027,6 +5043,7 @@ declare namespace ts.server.protocol {
         DocCommentTemplate = "docCommentTemplate",
         CompilerOptionsForInferredProjects = "compilerOptionsForInferredProjects",
         GetCodeFixes = "getCodeFixes",
+        GetCombinedCodeFix = "getCombinedCodeFix",
         ApplyCodeActionCommand = "applyCodeActionCommand",
         GetSupportedCodeFixes = "getSupportedCodeFixes",
         GetApplicableRefactors = "getApplicableRefactors",
@@ -5389,6 +5406,13 @@ declare namespace ts.server.protocol {
         command: CommandTypes.GetCodeFixes;
         arguments: CodeFixRequestArgs;
     }
+    interface GetCombinedCodeFixRequest extends Request {
+        command: CommandTypes.GetCombinedCodeFix;
+        arguments: GetCombinedCodeFixRequestArgs;
+    }
+    interface GetCombinedCodeFixResponse extends Response {
+        body: CombinedCodeActions;
+    }
     interface ApplyCodeActionCommandRequest extends Request {
         command: CommandTypes.ApplyCodeActionCommand;
         arguments: ApplyCodeActionCommandRequestArgs;
@@ -5422,6 +5446,14 @@ declare namespace ts.server.protocol {
          */
         errorCodes?: ReadonlyArray<number>;
     }
+    interface GetCombinedCodeFixRequestArgs {
+        scope: GetCombinedCodeFixScope;
+        fixId: {};
+    }
+    interface GetCombinedCodeFixScope {
+        type: "file";
+        args: FileRequestArgs;
+    }
     interface ApplyCodeActionCommandRequestArgs {
         /** May also be an array of commands. */
         command: {};
@@ -6164,7 +6196,7 @@ declare namespace ts.server.protocol {
     }
     interface CodeFixResponse extends Response {
         /** The code actions that are available */
-        body?: CodeAction[];
+        body?: CodeFixAction[];
     }
     interface CodeAction {
         /** Description of the code action to display in the UI of the editor */
@@ -6174,6 +6206,17 @@ declare namespace ts.server.protocol {
         /** A command is an opaque object that should be passed to `ApplyCodeActionCommandRequestArgs` without modification.  */
         commands?: {}[];
     }
+    interface CombinedCodeActions {
+        changes: ReadonlyArray<FileCodeEdits>;
+        commands?: ReadonlyArray<{}>;
+    }
+    interface CodeFixAction extends CodeAction {
+        /**
+         * If present, one may call 'getCombinedCodeFix' with this fixId.
+         * This may be omitted to indicate that the code fix can't be applied in a group.
+         */
+        fixId?: {};
+    }
     /**
      * Format and format on key response message.
      */
diff --git a/tests/baselines/reference/api/typescript.d.ts b/tests/baselines/reference/api/typescript.d.ts
index ce90fef044e..d5259f39f7f 100644
--- a/tests/baselines/reference/api/typescript.d.ts
+++ b/tests/baselines/reference/api/typescript.d.ts
@@ -4091,7 +4091,8 @@ declare namespace ts {
         getDocCommentTemplateAtPosition(fileName: string, position: number): TextInsertion;
         isValidBraceCompletionAtPosition(fileName: string, position: number, openingBrace: number): boolean;
         getSpanOfEnclosingComment(fileName: string, position: number, onlyMultiLine: boolean): TextSpan;
-        getCodeFixesAtPosition(fileName: string, start: number, end: number, errorCodes: ReadonlyArray<number>, formatOptions: FormatCodeSettings): ReadonlyArray<CodeAction>;
+        getCodeFixesAtPosition(fileName: string, start: number, end: number, errorCodes: ReadonlyArray<number>, formatOptions: FormatCodeSettings): ReadonlyArray<CodeFixAction>;
+        getCombinedCodeFix(scope: CombinedCodeFixScope, fixId: {}, formatOptions: FormatCodeSettings): CombinedCodeActions;
         applyCodeActionCommand(action: CodeActionCommand): Promise<ApplyCodeActionCommandResult>;
         applyCodeActionCommand(action: CodeActionCommand[]): Promise<ApplyCodeActionCommandResult[]>;
         applyCodeActionCommand(action: CodeActionCommand | CodeActionCommand[]): Promise<ApplyCodeActionCommandResult | ApplyCodeActionCommandResult[]>;
@@ -4107,6 +4108,10 @@ declare namespace ts {
         getProgram(): Program;
         dispose(): void;
     }
+    interface CombinedCodeFixScope {
+        type: "file";
+        fileName: string;
+    }
     interface GetCompletionsAtPositionOptions {
         includeExternalModuleExports: boolean;
         includeInsertTextCompletions: boolean;
@@ -4184,6 +4189,17 @@ declare namespace ts {
          */
         commands?: CodeActionCommand[];
     }
+    interface CodeFixAction extends CodeAction {
+        /**
+         * If present, one may call 'getCombinedCodeFix' with this fixId.
+         * This may be omitted to indicate that the code fix can't be applied in a group.
+         */
+        fixId?: {};
+    }
+    interface CombinedCodeActions {
+        changes: ReadonlyArray<FileTextChanges>;
+        commands: ReadonlyArray<CodeActionCommand> | undefined;
+    }
     type CodeActionCommand = InstallPackageAction;
     interface InstallPackageAction {
     }