Roblox Studio MCP Server

Instructions

Implementation Reference

• src/tools/index.ts:78-91 (handler)

  The core handler function that validates the instancePath input, makes an HTTP request to the Studio bridge for instance properties, and formats the JSON response for MCP.

  async getInstanceProperties(instancePath: string) {
    if (!instancePath) {
      throw new Error('Instance path is required for get_instance_properties');
    }
    const response = await this.client.request('/api/instance-properties', { instancePath });
    return {
      content: [
        {
          type: 'text',
          text: JSON.stringify(response, null, 2)
        }
      ]
    };
  }

• src/index.ts:141-153 (schema)

  The input schema definition registered for listTools, specifying the required 'instancePath' parameter and tool description.

    name: 'get_instance_properties',
    description: 'Get all properties of a specific instance',
    inputSchema: {
      type: 'object',
      properties: {
        instancePath: {
          type: 'string',
          description: 'Path to the instance'
        }
      },
      required: ['instancePath']
    }
  },

• src/index.ts:662-663 (registration)

  The MCP server request handler dispatches 'get_instance_properties' calls to the tools.getInstanceProperties method.

  case 'get_instance_properties':
    return await this.tools.getInstanceProperties((args as any)?.instancePath as string);

• src/http-server.ts:186-193 (registration)

  HTTP endpoint registration that proxies direct HTTP calls to the getInstanceProperties tool handler for Studio plugin compatibility.

  app.post('/mcp/get_instance_properties', async (req, res) => {
    try {
      const result = await tools.getInstanceProperties(req.body.instancePath);
      res.json(result);
    } catch (error) {
      res.status(500).json({ error: error instanceof Error ? error.message : 'Unknown error' });
    }
  });