RPG Maker MZ MCP Server

Instructions

Implementation Reference

• src/game-creation-tools.ts:250-257 (handler)

  The core handler function that reads Classes.json, adds a default class entry at the given ID with the specified name using getDefaultClass helper, writes back the JSON, and returns success with the ID.

  export async function addClass(projectPath: string, id: number, name: string) {
    const classesPath = path.join(projectPath, "data", "Classes.json");
    const classesContent = await fs.readFile(classesPath, "utf-8");
    const classes = JSON.parse(classesContent);
  
    classes[id] = getDefaultClass(id, name);
    await fs.writeFile(classesPath, JSON.stringify(classes, null, 0), "utf-8");
    return { success: true, id };

• src/index.ts:381-401 (schema)

  The input schema definition for the 'add_class' tool, specifying parameters project_path (string), id (number), name (string), all required. Listed in the tools response.

    name: "add_class",
    description: "Add a new class to the database",
    inputSchema: {
      type: "object",
      properties: {
        project_path: {
          type: "string",
          description: "Path to the RPG Maker MZ project directory",
        },
        id: {
          type: "number",
          description: "Class ID",
        },
        name: {
          type: "string",
          description: "Class name",
        },
      },
      required: ["project_path", "id", "name"],
    },
  },

• src/index.ts:1216-1223 (registration)

  The MCP tool call handler registration in the switch statement that extracts arguments, calls the addClass function, and returns the result as text content.

  case "add_class": {
    const projectPath = args.project_path as string;
    const id = args.id as number;
    const name = args.name as string;
    const result = await addClass(projectPath, id, name);
    return {
      content: [{ type: "text", text: JSON.stringify(result, null, 2) }],
    };