Gdharness
A harness for driving a Godot 4 project from an agent: addons, runtime bridge, MCP server, CLI.
Runs on your machine from its package; the steps are below.
What it does
- Reads
- Writes
- High impact
At most: moves money, runs code or commands, deletes data, or sends messages for you.
What it costs
FreeOdel charges nothing per call. The publisher may charge for its own service.
Runs locally over stdio
This server isn't hosted — your MCP client launches it from a package registry. Use one of the commands below, or drop the config into your client (e.g. Claude Desktop).
Run
npx -y gdharness
MCP client config
{
"mcpServers": {
"gdharness": {
"command": "npx",
"args": [
"-y",
"gdharness"
]
}
}
}
An agent cannot see a running game. It reads your scripts and guesses at the rest: whether the button is on screen, whether the panel updated, whether that error mattered.
gdharness makes the engine answerable instead. What the screen says, where a control is, what a property reads right now, what the console printed, what broke and on which line.
Install
Hand this to your agent:
Install gdharness here by following https://aureliolo.github.io/gdharness/agent.md,
then tell me what it asked you to recommend back to me.
Or do it yourself, and pick your harness: aureliolo.github.io/gdharness.
The loop it exists for
editor_run { "op": "start", "projectPath": "C:/games/hall" }
runtime_inspect { "op": "find", "says": "Buy" } // the button, by the word on it
runtime_input { "op": "click", "nodePath": "/root/Hall/Ledger/BuyButton" }
runtime_inspect { "op": "text", "nodePath": "/root/Hall/Ledger" } // what the panel says now
editor_output { "projectPath": "C:/games/hall" } // errors and warnings, with backtraces
The open editor plays the game, so its debugger holds it, which is what lets you set a breakpoint and read the variables in scope when it stops.
Every answer is read back out of the engine after the fact, never echoed from the request. A tool that cannot answer says which state it is in and what would change it, rather than answering emptily, so a call that succeeded is a call that was understood.
At a glance
| Needs | Godot 4.7 or newer, Node 22 or newer. Runs under Bun 1.4 too. |
| Surface | 30 tools named domain_verb, and 4 godot:// resources |
| Reaches | The editor that is open, a game it is playing, and the project on disk |
| Harnesses | 35, written inside the project wherever the harness has a project config |
| Skill | Written to .agents/skills, which every major harness reads |
| Install | npm, or a Sigstore-signed archive with an SBOM, SLSA Build Level 3 |
| Proven | Every tool driven against Godot 4.7.2 in CI, on Windows, Linux and macOS |
| Status | 1.0: every release is a patch. What a bump means |
Older 4.x is likely to work and is not tested.
Documentation
aureliolo.github.io/gdharness: installing it, how the parts connect, and every tool, op and argument.
SECURITY.md is how to report something. CONTRIBUTING.md is what a change has to clear.
Project
Fork of GoPeak v2.3.9, September 2026, MIT: the original MCP server godot-mcp by Solomon Elias, GoPeak by HaD0Yun, and completely reworked since to be hardened, condensed and more streamlined.
Not affiliated with the Godot Foundation.
