diff --git a/packages/compiler-cli/src/ngtsc/diagnostics/index.ts b/packages/compiler-cli/src/ngtsc/diagnostics/index.ts
index 58513e7c934..fcd7f120989 100644
--- a/packages/compiler-cli/src/ngtsc/diagnostics/index.ts
+++ b/packages/compiler-cli/src/ngtsc/diagnostics/index.ts
@@ -6,7 +6,6 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-export {COMPILER_ERRORS_WITH_GUIDES, ERROR_DETAILS_PAGE_BASE_URL} from './src/docs';
 export {FatalDiagnosticError, isFatalDiagnosticError, makeDiagnostic, makeRelatedInformation} from './src/error';
-export {ErrorCode} from './src/error_code';
-export {ngErrorCode, replaceTsWithNgInErrors} from './src/util';
+export {COMPILER_ERRORS_WITH_GUIDES, ERROR_DETAILS_PAGE_BASE_URL, ErrorCode, ngErrorCode} from './src/error_code';
+export {replaceTsWithNgInErrors} from './src/util';
diff --git a/packages/compiler-cli/src/ngtsc/diagnostics/src/docs.ts b/packages/compiler-cli/src/ngtsc/diagnostics/src/docs.ts
deleted file mode 100644
index 28c0a90dae0..00000000000
--- a/packages/compiler-cli/src/ngtsc/diagnostics/src/docs.ts
+++ /dev/null
@@ -1,30 +0,0 @@
-/**
- * @license
- * Copyright Google LLC All Rights Reserved.
- *
- * Use of this source code is governed by an MIT-style license that can be
- * found in the LICENSE file at https://angular.io/license
- */
-
-import {ErrorCode} from './error_code';
-
-/**
- * Base URL for the error details page.
- * Keep this value in sync with a similar const in
- * `packages/core/src/render3/error_code.ts`.
- */
-export const ERROR_DETAILS_PAGE_BASE_URL = 'https://angular.io/errors';
-
-/**
- * Contains a set of error messages that have detailed guides at angular.io.
- * Full list of available error guides can be found at https://angular.io/errors
- */
-export const COMPILER_ERRORS_WITH_GUIDES = new Set([
-  ErrorCode.DECORATOR_ARG_NOT_LITERAL,
-  ErrorCode.IMPORT_CYCLE_DETECTED,
-  ErrorCode.PARAM_MISSING_TOKEN,
-  ErrorCode.SCHEMA_INVALID_ELEMENT,
-  ErrorCode.SCHEMA_INVALID_ATTRIBUTE,
-  ErrorCode.MISSING_REFERENCE_TARGET,
-  ErrorCode.COMPONENT_INVALID_SHADOW_DOM_SELECTOR,
-]);
diff --git a/packages/compiler-cli/src/ngtsc/diagnostics/src/error.ts b/packages/compiler-cli/src/ngtsc/diagnostics/src/error.ts
index 2c1d40e9baf..0822840a9aa 100644
--- a/packages/compiler-cli/src/ngtsc/diagnostics/src/error.ts
+++ b/packages/compiler-cli/src/ngtsc/diagnostics/src/error.ts
@@ -8,8 +8,7 @@
 
 import * as ts from 'typescript';
 
-import {ErrorCode} from './error_code';
-import {ngErrorCode} from './util';
+import {ErrorCode, ngErrorCode} from './error_code';
 
 export class FatalDiagnosticError {
   constructor(
diff --git a/packages/compiler-cli/src/ngtsc/diagnostics/src/error_code.ts b/packages/compiler-cli/src/ngtsc/diagnostics/src/error_code.ts
index f791145f786..0adb4704db2 100644
--- a/packages/compiler-cli/src/ngtsc/diagnostics/src/error_code.ts
+++ b/packages/compiler-cli/src/ngtsc/diagnostics/src/error_code.ts
@@ -226,3 +226,33 @@ export enum ErrorCode {
    */
   SUGGEST_SUBOPTIMAL_TYPE_INFERENCE = 10002,
 }
+
+/**
+ * @internal
+ * Base URL for the error details page.
+ * Keep this value in sync with a similar const in
+ * `packages/core/src/render3/error_code.ts`.
+ */
+export const ERROR_DETAILS_PAGE_BASE_URL = 'https://angular.io/errors';
+
+/**
+ * @internal
+ * Contains a set of error messages that have detailed guides at angular.io.
+ * Full list of available error guides can be found at https://angular.io/errors
+ */
+export const COMPILER_ERRORS_WITH_GUIDES = new Set([
+  ErrorCode.DECORATOR_ARG_NOT_LITERAL,
+  ErrorCode.IMPORT_CYCLE_DETECTED,
+  ErrorCode.PARAM_MISSING_TOKEN,
+  ErrorCode.SCHEMA_INVALID_ELEMENT,
+  ErrorCode.SCHEMA_INVALID_ATTRIBUTE,
+  ErrorCode.MISSING_REFERENCE_TARGET,
+  ErrorCode.COMPONENT_INVALID_SHADOW_DOM_SELECTOR,
+]);
+
+/**
+ * @internal
+ */
+export function ngErrorCode(code: ErrorCode): number {
+  return parseInt('-99' + code);
+}
diff --git a/packages/compiler-cli/src/ngtsc/diagnostics/src/util.ts b/packages/compiler-cli/src/ngtsc/diagnostics/src/util.ts
index 898a3a1d446..7655d3c90d0 100644
--- a/packages/compiler-cli/src/ngtsc/diagnostics/src/util.ts
+++ b/packages/compiler-cli/src/ngtsc/diagnostics/src/util.ts
@@ -6,8 +6,6 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {ErrorCode} from './error_code';
-
 const ERROR_CODE_MATCHER = /(\u001b\[\d+m ?)TS-99(\d+: ?\u001b\[\d+m)/g;
 
 /**
@@ -22,7 +20,3 @@ const ERROR_CODE_MATCHER = /(\u001b\[\d+m ?)TS-99(\d+: ?\u001b\[\d+m)/g;
 export function replaceTsWithNgInErrors(errors: string): string {
   return errors.replace(ERROR_CODE_MATCHER, '$1NG$2');
 }
-
-export function ngErrorCode(code: ErrorCode): number {
-  return parseInt('-99' + code);
-}
diff --git a/packages/core/src/render3/error_code.ts b/packages/core/src/render3/error_code.ts
index 700d5eded38..84be7f56be1 100644
--- a/packages/core/src/render3/error_code.ts
+++ b/packages/core/src/render3/error_code.ts
@@ -8,7 +8,7 @@
 
 // Base URL for the error details page.
 // Keep this value in sync with a similar const in
-// `packages/compiler-cli/src/ngtsc/diagnostics/src/docs.ts`.
+// `packages/compiler-cli/src/ngtsc/diagnostics/src/error_code.ts`.
 const ERROR_DETAILS_PAGE_BASE_URL = 'https://angular.io/errors';
 
 export const enum RuntimeErrorCode {