Summer Engine MCP guide
How to make games in OpenCode with Summer Engine
Use OpenCode with Summer Engine MCP to build real game projects in a running editor with export-ready project files. Summer Engine is the desktop game engine; OpenCode 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 OpenCode
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 OpenCode
- 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 OpenCode
Writes the summer-engine MCP config and installs the Summer game-dev skills.
- 4
Restart and build
Restart OpenCode so it reloads opencode.json.
Why this matters
OpenCode writes with your subscription. Summer Engine shows the game.
A chat agent alone can write files. With MCP, OpenCode gets tools for the running game engine, so it can inspect the project, run commands, and make changes that become playable inside Summer.