Phase 1 complete

apps/backend/src/chat/dto/chat.dto.ts

@@ -0,0 +1,25 @@
+import { IsString, IsOptional } from 'class-validator';
+import { ApiProperty, ApiPropertyOptional } from '@nestjs/swagger';
+
+export class CreateConversationDto {
+  @ApiProperty({ description: 'Character ID to chat with', example: '550e8400-e29b-41d4-a716-446655440000' })
+  @IsString()
+  characterId: string;
+
+  @ApiPropertyOptional({ description: 'Conversation title', example: 'My Adventure with Alice' })
+  @IsOptional()
+  @IsString()
+  title?: string;
+}
+
+export class SendMessageDto {
+  @ApiProperty({ description: 'Message content', example: 'Hello! Tell me about yourself.' })
+  @IsString()
+  content: string;
+}
+
+export class UpdateMessageDto {
+  @ApiProperty({ description: 'Updated message content' })
+  @IsString()
+  content: string;
+}