RPG Maker MZ MCP Server

Instructions

Implementation Reference

• src/index.ts:473-502 (schema)

  Input schema definition for the 'generate_asset' MCP tool, specifying parameters like project_path, asset_type, prompt, filename, and optional api_key.
  name: "generate_asset", description: "Generate RPG Maker MZ asset using Gemini 2.5 Flash (characters, faces, tilesets, etc.)", inputSchema: { type: "object", properties: { project_path: { type: "string", description: "Path to the RPG Maker MZ project directory", }, asset_type: { type: "string", enum: ["character", "face", "tileset", "battleback", "enemy", "sv_actor", "picture"], description: "Type of asset to generate", }, prompt: { type: "string", description: "Description of the asset to generate", }, filename: { type: "string", description: "Filename for the generated asset (with extension)", }, api_key: { type: "string", description: "Gemini API key (optional, uses GEMINI_API_KEY env var if not provided)", }, }, required: ["project_path", "asset_type", "prompt", "filename"], }, },
• src/index.ts:1257-1269 (handler)

  MCP tool dispatcher handler for 'generate_asset' that constructs AssetGenerationRequest and calls generateAssetWithGemini.
  case "generate_asset": { const request: AssetGenerationRequest = { projectPath: args.project_path as string, assetType: args.asset_type as any, prompt: args.prompt as string, filename: args.filename as string, apiKey: args.api_key as string | undefined, }; const result = await generateAssetWithGemini(request); return { content: [{ type: "text", text: JSON.stringify(result, null, 2) }], }; }
• src/asset-generation.ts:41-117 (handler)

  Core implementation of asset generation using Gemini API: validates input, builds enhanced prompt, calls API, extracts image data, saves to project directory.
  export async function generateAssetWithGemini(request: AssetGenerationRequest): Promise<{ success: boolean; path?: string; error?: string }> { try { // Validate inputs await validateProjectPath(request.projectPath); Validator.requireEnum( request.assetType, "assetType", ["character", "face", "tileset", "battleback", "enemy", "sv_actor", "picture"] as const ); Validator.requireString(request.prompt, "prompt"); Validator.requireString(request.filename, "filename"); const apiKey = validateGeminiAPIKey(request.apiKey); await Logger.info("Generating asset with Gemini", { projectPath: request.projectPath, assetType: request.assetType, filename: request.filename }); const specs = ASSET_SPECS[request.assetType]; const enhancedPrompt = buildPrompt(request.assetType, request.prompt, specs); // Call Gemini 2.5 Flash API with image generation const response = await APIHelper.fetchWithRetry( `https://generativelanguage.googleapis.com/v1beta/models/gemini-2.0-flash-exp:generateContent?key=${apiKey}`, { method: "POST", headers: { "Content-Type": "application/json", }, body: JSON.stringify({ contents: [{ parts: [{ text: enhancedPrompt }] }], generationConfig: { temperature: 1.0, topK: 40, topP: 0.95, maxOutputTokens: 8192, } }) } ); if (!response.ok) { return { success: false, error: `API error: ${response.statusText}` }; } const data = await response.json(); // Extract image data (assuming Gemini returns base64 or URL) // Note: Gemini 2.5 Flash may not support direct image generation // This is a placeholder for the actual implementation const imageData = extractImageData(data); if (!imageData) { return { success: false, error: "No image data in response" }; } // Save image to appropriate directory const assetPath = getAssetPath(request.projectPath, request.assetType); await fs.mkdir(assetPath, { recursive: true }); const fullPath = path.join(assetPath, request.filename); await saveImage(fullPath, imageData); return { success: true, path: fullPath }; } catch (error) { return { success: false, error: error instanceof Error ? error.message : String(error) }; } }
• src/asset-generation.ts:13-19 (schema)

  TypeScript interface defining the input parameters for asset generation, matching the MCP tool schema.
  export interface AssetGenerationRequest { projectPath: string; assetType: "character" | "face" | "tileset" | "battleback" | "enemy" | "sv_actor" | "picture"; prompt: string; filename: string; apiKey?: string; }
• src/index.ts:24-24 (helper)

  Import of the generateAssetWithGemini handler and AssetGenerationRequest type from asset-generation.ts.
  generateAssetWithGemini,