diff --git a/pkg/analysis_server/messages.yaml b/pkg/analysis_server/messages.yaml
new file mode 100644
index 00000000000..c2299f486cd
--- /dev/null
+++ b/pkg/analysis_server/messages.yaml
@@ -0,0 +1,130 @@
+# Copyright (c) 2025, the Dart project authors.  Please see the AUTHORS file
+# for details. All rights reserved. Use of this source code is governed by a
+# BSD-style license that can be found in the LICENSE file.
+
+# Run
+#
+#     dart run pkg/analyzer/tool/messages/generate.dart
+#
+# to regenerate messages after having edited this file.
+
+# See `pkg/analyzer/messages.yaml` for a description of the contents
+# of this file.
+
+TransformSetErrorCode:
+  conflicting_key:
+    parameters:
+      Object p0: the conflicting key
+      Object p1: the key that it conflicts with
+    problemMessage: "The key '#p0' can't be used when '#p1' is also used."
+    hasPublishedDocs: false
+  expected_primary:
+    parameters: none
+    problemMessage: "Expected either an identifier or a string literal."
+    hasPublishedDocs: false
+  incompatible_element_kind:
+    parameters:
+      Object p0: the old kind
+      Object p1: the new kind
+    problemMessage: "An element of kind '#p0' can't be replaced by an element of kind '#p1'."
+    hasPublishedDocs: false
+  invalid_change_for_kind:
+    parameters:
+      Object p0: the change kind that is invalid
+      Object p1: the element kind for the transform
+    problemMessage: "A change of type '#p0' can't be used for an element of kind '#p1'."
+    hasPublishedDocs: false
+  invalid_character:
+    parameters:
+      Object p0: the character that is invalid
+    problemMessage: "Invalid character '#p0'."
+    hasPublishedDocs: false
+  invalid_key:
+    parameters:
+      Object p0: the actual type of the key
+    problemMessage: "Keys must be of type 'String' but found the type '#p0'."
+    hasPublishedDocs: false
+  invalid_required_if:
+    parameters: none
+    problemMessage: "The key 'requiredIf' can only be used with optional named parameters."
+    hasPublishedDocs: false
+  invalid_value:
+    parameters:
+      Object p0: the key with which the value is associated
+      Object p1: the expected type of the value
+      Object p2: the actual type of the value
+    problemMessage: "The value of '#p0' should be of type '#p1' but is of type '#p2'."
+    hasPublishedDocs: false
+  invalid_parameter_style:
+    parameters:
+      Object p0: the list of valid parameter styles
+    problemMessage: "The parameter style must be one of the following: #p0."
+    hasPublishedDocs: false
+  invalid_value_one_of:
+    parameters:
+      Object p0: the key with which the value is associated
+      Object p1: the allowed values as a comma-separated list
+    problemMessage: "The value of '#p0' must be one of the following: '#p1'."
+    hasPublishedDocs: false
+  missing_key:
+    parameters:
+      Object p0: the missing key
+    problemMessage: "Missing the required key '#p0'."
+    hasPublishedDocs: false
+  missing_one_of_multiple_keys:
+    parameters:
+      Object p0: the list of valid keys
+    problemMessage: "Exactly one of the following keys must be provided: #p0."
+    hasPublishedDocs: false
+  missing_template_end:
+    parameters: none
+    problemMessage: "Missing the end brace for the template."
+    hasPublishedDocs: false
+  missing_token:
+    parameters:
+      Object p0: a description of the expected kinds of tokens
+    problemMessage: "Expected to find #p0."
+    hasPublishedDocs: false
+  missing_uri:
+    parameters: none
+    problemMessage: "At least one URI must be provided."
+    hasPublishedDocs: false
+  undefined_variable:
+    parameters:
+      Object p0: the missing key
+    problemMessage: "The variable '#p0' isn't defined."
+    hasPublishedDocs: false
+  unexpected_transform_set_token:
+    parameters:
+      Object p0: the token that was unexpectedly found
+    problemMessage: "Didn't expect to find #p0."
+    hasPublishedDocs: false
+  unknown_accessor:
+    parameters:
+      Object p0: a description of the expected kind of token
+    problemMessage: "The accessor '#p0' is invalid."
+    hasPublishedDocs: false
+  unsupported_key:
+    parameters:
+      Object p0: the unsupported key
+    problemMessage: "The key '#p0' isn't supported."
+    hasPublishedDocs: false
+  unsupported_static:
+    parameters: none
+    problemMessage: "The key 'static' is only supported for elements in a class, enum, extension, or mixin."
+    hasPublishedDocs: false
+  unsupported_version:
+    parameters: none
+    problemMessage: "Only version '1' is supported at this time."
+    hasPublishedDocs: false
+  wrong_token:
+    parameters:
+      Object p0: a description of the expected kind of token
+      Object p1: a description of the actual kind of token
+    problemMessage: "Expected to find #p0, but found #p1."
+    hasPublishedDocs: false
+  yaml_syntax_error:
+    parameters:
+      Object p0: the message produced by the YAML parser
+    problemMessage: "Parse error: #p0"
+    hasPublishedDocs: false
diff --git a/pkg/analyzer/messages.yaml b/pkg/analyzer/messages.yaml
index caa5d0a4741..254626b6109 100644
--- a/pkg/analyzer/messages.yaml
+++ b/pkg/analyzer/messages.yaml
@@ -23302,123 +23302,6 @@ TodoCode:
     hasPublishedDocs: false
     comment: |-
       A TODO comment marked as UNDONE.
-TransformSetErrorCode:
-  conflicting_key:
-    parameters:
-      Object p0: the conflicting key
-      Object p1: the key that it conflicts with
-    problemMessage: "The key '#p0' can't be used when '#p1' is also used."
-    hasPublishedDocs: false
-  expected_primary:
-    parameters: none
-    problemMessage: "Expected either an identifier or a string literal."
-    hasPublishedDocs: false
-  incompatible_element_kind:
-    parameters:
-      Object p0: the old kind
-      Object p1: the new kind
-    problemMessage: "An element of kind '#p0' can't be replaced by an element of kind '#p1'."
-    hasPublishedDocs: false
-  invalid_change_for_kind:
-    parameters:
-      Object p0: the change kind that is invalid
-      Object p1: the element kind for the transform
-    problemMessage: "A change of type '#p0' can't be used for an element of kind '#p1'."
-    hasPublishedDocs: false
-  invalid_character:
-    parameters:
-      Object p0: the character that is invalid
-    problemMessage: "Invalid character '#p0'."
-    hasPublishedDocs: false
-  invalid_key:
-    parameters:
-      Object p0: the actual type of the key
-    problemMessage: "Keys must be of type 'String' but found the type '#p0'."
-    hasPublishedDocs: false
-  invalid_required_if:
-    parameters: none
-    problemMessage: "The key 'requiredIf' can only be used with optional named parameters."
-    hasPublishedDocs: false
-  invalid_value:
-    parameters:
-      Object p0: the key with which the value is associated
-      Object p1: the expected type of the value
-      Object p2: the actual type of the value
-    problemMessage: "The value of '#p0' should be of type '#p1' but is of type '#p2'."
-    hasPublishedDocs: false
-  invalid_parameter_style:
-    parameters:
-      Object p0: the list of valid parameter styles
-    problemMessage: "The parameter style must be one of the following: #p0."
-    hasPublishedDocs: false
-  invalid_value_one_of:
-    parameters:
-      Object p0: the key with which the value is associated
-      Object p1: the allowed values as a comma-separated list
-    problemMessage: "The value of '#p0' must be one of the following: '#p1'."
-    hasPublishedDocs: false
-  missing_key:
-    parameters:
-      Object p0: the missing key
-    problemMessage: "Missing the required key '#p0'."
-    hasPublishedDocs: false
-  missing_one_of_multiple_keys:
-    parameters:
-      Object p0: the list of valid keys
-    problemMessage: "Exactly one of the following keys must be provided: #p0."
-    hasPublishedDocs: false
-  missing_template_end:
-    parameters: none
-    problemMessage: "Missing the end brace for the template."
-    hasPublishedDocs: false
-  missing_token:
-    parameters:
-      Object p0: a description of the expected kinds of tokens
-    problemMessage: "Expected to find #p0."
-    hasPublishedDocs: false
-  missing_uri:
-    parameters: none
-    problemMessage: "At least one URI must be provided."
-    hasPublishedDocs: false
-  undefined_variable:
-    parameters:
-      Object p0: the missing key
-    problemMessage: "The variable '#p0' isn't defined."
-    hasPublishedDocs: false
-  unexpected_transform_set_token:
-    parameters:
-      Object p0: the token that was unexpectedly found
-    problemMessage: "Didn't expect to find #p0."
-    hasPublishedDocs: false
-  unknown_accessor:
-    parameters:
-      Object p0: a description of the expected kind of token
-    problemMessage: "The accessor '#p0' is invalid."
-    hasPublishedDocs: false
-  unsupported_key:
-    parameters:
-      Object p0: the unsupported key
-    problemMessage: "The key '#p0' isn't supported."
-    hasPublishedDocs: false
-  unsupported_static:
-    parameters: none
-    problemMessage: "The key 'static' is only supported for elements in a class, enum, extension, or mixin."
-    hasPublishedDocs: false
-  unsupported_version:
-    parameters: none
-    problemMessage: "Only version '1' is supported at this time."
-    hasPublishedDocs: false
-  wrong_token:
-    parameters:
-      Object p0: a description of the expected kind of token
-      Object p1: a description of the actual kind of token
-    problemMessage: "Expected to find #p0, but found #p1."
-    hasPublishedDocs: false
-  yaml_syntax_error:
-    parameters:
-      Object p0: the message produced by the YAML parser
-    problemMessage: "Parse error: #p0"
-    hasPublishedDocs: false
 WarningCode:
   ARGUMENT_TYPE_NOT_ASSIGNABLE_TO_ERROR_HANDLER:
     parameters:
diff --git a/pkg/analyzer/test/verify_diagnostics_test.dart b/pkg/analyzer/test/verify_diagnostics_test.dart
index 447334a83c7..b27d7918c0e 100644
--- a/pkg/analyzer/test/verify_diagnostics_test.dart
+++ b/pkg/analyzer/test/verify_diagnostics_test.dart
@@ -220,6 +220,7 @@ class DocumentationValidator {
   Future<void> validate() async {
     await _validateMessages(feAnalyzerSharedMessages);
     await _validateMessages(analyzerMessages);
+    await _validateMessages(analysisServerMessages);
     await _validateMessages(lintMessages);
     if (buffer.isNotEmpty) {
       fail(buffer.toString());
diff --git a/pkg/analyzer_utilities/lib/analyzer_messages.dart b/pkg/analyzer_utilities/lib/analyzer_messages.dart
index 6e1ca1ac551..4f6488d169c 100644
--- a/pkg/analyzer_utilities/lib/analyzer_messages.dart
+++ b/pkg/analyzer_utilities/lib/analyzer_messages.dart
@@ -184,6 +184,16 @@ const transformSetErrorCodeFile = GeneratedDiagnosticFile(
   package: AnalyzerDiagnosticPackage.analysisServer,
 );
 
+/// Decoded messages from the analysis server's `messages.yaml` file.
+final List<AnalyzerMessage> analysisServerMessages = decodeAnalyzerMessagesYaml(
+  analysisServerPkgPath,
+);
+
+/// The path to the `analysis_server` package.
+final String analysisServerPkgPath = normalize(
+  join(pkg_root.packageRoot, 'analysis_server'),
+);
+
 /// Decoded messages from the analyzer's `messages.yaml` file.
 final List<AnalyzerMessage> analyzerMessages = decodeAnalyzerMessagesYaml(
   analyzerPkgPath,
diff --git a/pkg/analyzer_utilities/lib/messages.dart b/pkg/analyzer_utilities/lib/messages.dart
index b12c7ed0066..bed7c6bd08c 100644
--- a/pkg/analyzer_utilities/lib/messages.dart
+++ b/pkg/analyzer_utilities/lib/messages.dart
@@ -33,6 +33,7 @@ final DiagnosticTables diagnosticTables = DiagnosticTables._([
   ...frontEndMessages,
   ...feAnalyzerSharedMessages,
   ...analyzerMessages,
+  ...analysisServerMessages,
   ...lintMessages,
 ]);