diff --git a/scribe/lib/scribe/ai/data/model/ai_message.dart b/scribe/lib/scribe/ai/data/model/ai_message.dart
index e4cedee4e..985d22529 100644
--- a/scribe/lib/scribe/ai/data/model/ai_message.dart
+++ b/scribe/lib/scribe/ai/data/model/ai_message.dart
@@ -2,12 +2,16 @@ import 'package:json_annotation/json_annotation.dart';
 
 part 'ai_message.g.dart';
 
+enum AIRole {
+  @JsonValue('user')
+  user,
+  @JsonValue('system')
+  system,
+}
+
 @JsonSerializable()
 class AIMessage {
-  static const String aiUserRole = 'user';
-  static const String aiSystemRole = 'system';
-
-  final String role;
+  final AIRole role;
   final String content;
 
   const AIMessage({
@@ -21,12 +25,12 @@ class AIMessage {
   Map<String, dynamic> toJson() => _$AIMessageToJson(this);
 
   factory AIMessage.ofUser(String content) => AIMessage(
-        role: aiUserRole,
+        role: AIRole.user,
         content: content,
       );
 
   factory AIMessage.ofSystem(String content) => AIMessage(
-        role: aiSystemRole,
+        role: AIRole.system,
         content: content,
       );
 }
diff --git a/scribe/lib/scribe/ai/domain/model/prompt_data.dart b/scribe/lib/scribe/ai/domain/model/prompt_data.dart
index 14509de9b..abc062039 100644
--- a/scribe/lib/scribe/ai/domain/model/prompt_data.dart
+++ b/scribe/lib/scribe/ai/domain/model/prompt_data.dart
@@ -54,9 +54,9 @@ class Prompt {
   List<AIMessage> buildPrompt(String inputText, {String? task}) {
     final messages = <AIMessage>[];
     for (final message in this.messages) {
-      if (message.role == 'system') {
+      if (message.role == AIRole.system) {
         messages.add(AIMessage.ofSystem(message.content));
-      } else if (message.role == 'user') {
+      } else if (message.role == AIRole.user) {
         final userContent = _replacePlaceholders(message.content, inputText, task);
         messages.add(AIMessage.ofUser(userContent));
       }
diff --git a/scribe/test/scribe/ai/domain/model/prompt_data_test.dart b/scribe/test/scribe/ai/domain/model/prompt_data_test.dart
index 836d0c460..25e9846e3 100644
--- a/scribe/test/scribe/ai/domain/model/prompt_data_test.dart
+++ b/scribe/test/scribe/ai/domain/model/prompt_data_test.dart
@@ -85,17 +85,17 @@ void main() {
       // Assert
       expect(prompt.name, 'test-prompt');
       expect(prompt.messages.length, 2);
-      expect(prompt.messages.first.role, 'system');
+      expect(prompt.messages.first.role, AIRole.system);
       expect(prompt.messages.first.content, 'System message');
-      expect(prompt.messages.last.role, 'user');
+      expect(prompt.messages.last.role, AIRole.user);
       expect(prompt.messages.last.content, 'User message with {{input}} placeholder');
     });
 
     test('buildPrompt should replace input placeholder correctly', () {
       // Arrange
       final messages = [
-        const AIMessage(role: 'system', content: 'System message'),
-        const AIMessage(role: 'user', content: 'User message with {{input}} placeholder')
+        const AIMessage(role: AIRole.system, content: 'System message'),
+        const AIMessage(role: AIRole.user, content: 'User message with {{input}} placeholder')
       ];
       final prompt = Prompt(name: 'test-prompt', messages: messages);
 
@@ -104,17 +104,17 @@ void main() {
 
       // Assert
       expect(result.length, 2);
-      expect(result.first.role, 'system');
+      expect(result.first.role, AIRole.system);
       expect(result.first.content, 'System message');
-      expect(result.last.role, 'user');
+      expect(result.last.role, AIRole.user);
       expect(result.last.content, 'User message with test input value placeholder');
     });
 
     test('buildPrompt should replace task placeholder when provided', () {
       // Arrange
       final messages = [
-        const AIMessage(role: 'system', content: 'System message'),
-        const AIMessage(role: 'user', content: 'Task: {{task}}, Input: {{input}}')
+        const AIMessage(role: AIRole.system, content: 'System message'),
+        const AIMessage(role: AIRole.user, content: 'Task: {{task}}, Input: {{input}}')
       ];
       final prompt = Prompt(name: 'test-prompt', messages: messages);
 
@@ -123,17 +123,17 @@ void main() {
 
       // Assert
       expect(result.length, 2);
-      expect(result.first.role, 'system');
+      expect(result.first.role, AIRole.system);
       expect(result.first.content, 'System message');
-      expect(result.last.role, 'user');
+      expect(result.last.role, AIRole.user);
       expect(result.last.content, 'Task: test task value, Input: test input value');
     });
 
     test('buildPrompt should not replace task placeholder when not provided', () {
       // Arrange
       final messages = [
-        const AIMessage(role: 'system', content: 'System message'),
-        const AIMessage(role: 'user', content: 'Task: {{task}}, Input: {{input}}')
+        const AIMessage(role: AIRole.system, content: 'System message'),
+        const AIMessage(role: AIRole.user, content: 'Task: {{task}}, Input: {{input}}')
       ];
       final prompt = Prompt(name: 'test-prompt', messages: messages);
 
@@ -142,17 +142,17 @@ void main() {
 
       // Assert
       expect(result.length, 2);
-      expect(result.first.role, 'system');
+      expect(result.first.role, AIRole.system);
       expect(result.first.content, 'System message');
-      expect(result.last.role, 'user');
+      expect(result.last.role, AIRole.user);
       expect(result.last.content, 'Task: {{task}}, Input: test input value');
     });
 
     test('buildPrompt should handle messages without placeholders', () {
       // Arrange
       final messages = [
-        const AIMessage(role: 'system', content: 'System message'),
-        const AIMessage(role: 'user', content: 'User message without placeholders')
+        const AIMessage(role: AIRole.system, content: 'System message'),
+        const AIMessage(role: AIRole.user, content: 'User message without placeholders')
       ];
       final prompt = Prompt(name: 'test-prompt', messages: messages);
 
diff --git a/scribe/test/scribe/ai/domain/service/prompt_service_test.dart b/scribe/test/scribe/ai/domain/service/prompt_service_test.dart
index c40b13d63..f308f847a 100644
--- a/scribe/test/scribe/ai/domain/service/prompt_service_test.dart
+++ b/scribe/test/scribe/ai/domain/service/prompt_service_test.dart
@@ -27,8 +27,8 @@ void main() {
 
       // Assert
       expect(messages.length, 2);
-      expect(messages.first.role, 'system');
-      expect(messages.last.role, 'user');
+      expect(messages.first.role, AIRole.system);
+      expect(messages.last.role, AIRole.user);
       expect(messages.last.content, contains('Hello, how are you?'));
     });
 
@@ -41,8 +41,8 @@ void main() {
 
       // Assert
       expect(messages.length, 2);
-      expect(messages.first.role, 'system');
-      expect(messages.last.role, 'user');
+      expect(messages.first.role, AIRole.system);
+      expect(messages.last.role, AIRole.user);
       expect(messages.last.content, contains('Hello, how are you?'));
       expect(messages.last.content, contains('Make it more casual'));
     });
@@ -56,8 +56,8 @@ void main() {
           Prompt(
             name: 'test-prompt',
             messages: [
-              const AIMessage(role: 'system', content: 'System message'),
-              const AIMessage(role: 'user', content: 'User message with {{input}}')
+              const AIMessage(role: AIRole.system, content: 'System message'),
+              const AIMessage(role: AIRole.user, content: 'User message with {{input}}')
             ]
           )
         ]
@@ -81,8 +81,8 @@ void main() {
           Prompt(
             name: 'test-prompt',
             messages: [
-              const AIMessage(role: 'system', content: 'System message'),
-              const AIMessage(role: 'user', content: 'User message')
+              const AIMessage(role: AIRole.system, content: 'System message'),
+              const AIMessage(role: AIRole.user, content: 'User message')
             ]
           )
         ]