Summer Engine MCP guide
How to make games in Grok Build with Summer Engine
Connect Grok Build, the xAI coding agent, to Summer Engine so Grok can create scenes, write gameplay, run the game, and fix errors through MCP. Summer Engine is the desktop game engine; Grok Build is the agent that drives it through MCP.
Summer is free for MCP use
Download the desktop engine and connect it to your agent. You are not paying Summer for the AI calls your existing subscription already covers.
Open Grok Build
Use the AI editor you already have. The setup command writes the MCP config and installs the Summer game-dev skills.
Run a Summer game
The agent writes code. Summer Engine shows the Summer game, runs Play mode, and helps inspect errors. Export still requires the target templates and toolchains.
Install
Connect Summer to Grok Build
- 1
Install Summer Engine
Downloads the desktop engine app, about 1 GB. Skip it if Summer Engine is already installed, or if you only need assets and video for a game built in another engine.
- 2
Sign in
Opens your browser once. The CLI and the engine share the session.
- 3
Connect Grok Build
Writes the summer-engine MCP config and installs the Summer game-dev skills.
- 4
Restart and build
Restart Grok Build so it reloads config.toml (it also reads ~/.claude.json and .cursor/mcp.json).
Setup notes
The 2026 specifics.
Where the config goes
The setup command adds the summer-engine server to ~/.grok/config.toml. Grok Build also reads ~/.claude.json and .cursor/mcp.json, so an existing Claude Code or Cursor setup may already be visible to it.
Why this matters
Grok Build writes with your subscription. Summer Engine shows the game.
A chat agent alone can write files. With MCP, Grok Build gets tools for the running game engine, so it can inspect the project, run commands, and make changes that become playable inside Summer.