Godot MCP Runtime

<a href="https://glama.ai/mcp/servers/@Erodenn/godot-mcp-runtime"> </a>  A lightweight MCP server that gives AI assistants direct access to a running Godot 4.x game. Not just file editing, not just scene manipulation. Actual runtime control: input simulation, screenshots, UI discovery, and live GDScript execution while the game is running. The distinction matters: the AI doesn't just write your game, it can check its work. When you run a project through this server, it injects a lightweight UDP bridge as an autoload, and suddenly the AI can interact with your game the same way a player would: press keys, click buttons, read what's on screen, and run arbitrary code against the live scene tree. No addon required. Most Godot MCP servers that offer runtime support ship as a Godot addon — something you install into your project, commit to version control, and manage as a dependency. All this server needs is Node.js and a Godot executable: no addon installation, no project modifications, no cleanup. Think of it as Playwright MCP, but for Godot. This does the same thing for games: run the project, take a screenshot, simulate input, read what's on screen, execute a script against the live scene tree. The agent closes the loop on its own changes rather than handing off to you to verify. This is not a playtesting replacement. It doesn't catch the subtle feel issues that only a human notices, and it won't tell you if your game is fun. What it does is let an agent confirm that a scene loads, a button responds, a value updated, a script ran without errors. The ability to check work is crucial for AI driven workflows. Each tool teaches agents how to use it through its description and response messages: what to call next, when to wait, and how to recover from errors. Every operation is its own tool with only its relevant parameters, no operation discriminators and no conditional schemas. This server is built for agents.

What It Does

Headless editing. Create scenes, add nodes, set properties, attach scripts, connect signals, manage UIDs, validate GDScript. All the standard operations, no editor window required. Runtime bridge. When run_project or attach_project is called, the server injects McpBridge as an autoload. This opens a UDP channel on port 9900 (localhost only) and enables: - Screenshots: Capture the viewport at any point during gameplay - Input simulation: Batched sequences of key presses, mouse clicks, mouse motion, UI element clicks by name or path, Godot action events, and timed waits - UI discovery: Walk the live scene tree and collect every visible Control node with its position, type, text content, and disabled state - Live script execution: Compile and run arbitrary GDScript with full SceneTree access while the game is running Background mode. Pass background: true to run_project and the Godot window moves off-screen with physical input blocked: borderless, unfocusable, mouse-passthrough. Programmatic input, screenshots, and all runtime tools work exactly the same. Useful for automated agent-driven testing where the window shouldn't be visible or interactive. Manual attach mode. When something other than MCP launches the game (a CI pipeline, an external debugger, your own shell), call attach_project first. It injects the bridge and marks the project active without spawning Godot, so when you launch the game manually, runtime tools work against it. The tradeoff: get_debug_output is unavailable in attached mode because stdout and stderr only flow through processes MCP started itself. Use detach_project when done. The bridge cleans itself up automatically when stop_project or detach_project is called. No leftover autoloads, no modified project files.

Quick Start

Prerequisites

- Node.js v18+ - Godot 4.x That's it. No Godot addon, no project modifications.

Configure Your MCP Client

Add the following to your MCP client config. Works with Claude Code, Claude Desktop, Cursor, or any MCP-compatible client. Zero-install via npx (recommended): ``json { "mcpServers": { "godot": { "command": "npx", "args": ["-y", "godot-mcp-runtime"], "env": { "GODOT_PATH": "<path-to-godot-executable>" } } } } ` Or install globally: `bash npm install -g godot-mcp-runtime ` `json { "mcpServers": { "godot": { "command": "godot-mcp-runtime", "env": { "GODOT_PATH": "<path-to-godot-executable>" } } } } ` Or clone from source: `bash git clone https://github.com/Erodenn/godot-mcp-runtime.git cd godot-mcp-runtime npm install npm run build ` `json { "mcpServers": { "godot": { "command": "node", "args": ["<path-to>/godot-mcp-runtime/dist/index.js"], "env": { "GODOT_PATH": "<path-to-godot-executable>" } } } } ` If Godot is on your PATH, you can omit GODOT_PATH entirely. The server will auto-detect it. Set "DEBUG": "true" in env for verbose logging.

Verify

Ask your AI assistant to call get_project_info. If it returns a Godot version string (e.g., 4.4.stable), you're connected and working.

Tools

Project Management

| Tool | Description | | ------------------ | -------------------------------------------------------------------------------------- | | launch_editor | Open the Godot editor GUI for a project | | run_project | Run a project and inject the MCP bridge. Pass background: true to hide the window | | attach_project | Inject the MCP bridge for a project you'll launch yourself | | detach_project | Remove the injected bridge after manual-launch use, leaving the external process alone | | stop_project | Stop the running project and remove the bridge (also detaches attached-mode state) | | get_debug_output | Read stdout/stderr from an MCP-spawned project (unavailable in attached mode) | | list_projects | Find Godot projects in a directory | | get_project_info | Get project metadata and Godot version |

Runtime (requires run_project or attach_project first)

After run_project, or after attach_project plus launching Godot manually, wait 2-3 seconds for the bridge to initialize before using these tools. | Tool | Description | | ----------------- | ---------------------------------------------------------------- | | take_screenshot | Capture a PNG of the running viewport | | simulate_input | Send batched input: key, mouse, click_element, action, wait | | get_ui_elements | Get all visible Control nodes with positions, types, and text | | run_script | Execute arbitrary GDScript at runtime with full SceneTree access |

Scene Editing (headless)

All mutation operations save automatically. Use save_scene only for save-as (newPath) or to re-canonicalize a .tscn file. | Tool | Description | | ------------------------ | -------------------------------------------------------------------- | | create_scene | Create a new scene file | | add_node | Add a node to an existing scene (supports promoted spatial params) | | load_sprite | Set a texture on a Sprite2D, Sprite3D, or TextureRect | | save_scene | Re-pack and save the scene, or save-as with newPath | | export_mesh_library | Export scenes as a MeshLibrary for GridMap | | batch_scene_operations | Run multiple add_node/load_sprite/save ops in a single Godot process |

Node Editing (headless)

All mutation operations save automatically. | Tool | Description | | --------------------------- | ------------------------------------------------------------------------- | | get_scene_tree | Get the full scene tree hierarchy (use maxDepth: 1 for shallow listing) | | get_node_properties | Read properties from a node | | batch_get_node_properties | Read properties from multiple nodes in one process | | set_node_property | Set a property on a node | | batch_set_node_properties | Set multiple properties in one process | | attach_script | Attach a GDScript to a node | | duplicate_node | Duplicate a node within the scene | | delete_node | Remove a node from the scene | | get_node_signals | List all signals on a node with their connections | | connect_signal | Connect a signal to a method on another node | | disconnect_signal | Disconnect a signal connection |

Project Config (no Godot process required)

These tools edit project.godot directly or read the filesystem. Safe to use even when autoloads are broken. | Tool | Description | | ------------------------ | ------------------------------------------------------------- | | list_autoloads | List all registered autoloads with paths and singleton status | | add_autoload | Register a new autoload | | remove_autoload | Unregister an autoload by name | | update_autoload | Modify an existing autoload's path or singleton flag | | get_project_settings | Read settings from project.godot by section and key | | get_project_files | Get the project file tree with types and extensions | | search_project | Search for a string across project source files | | get_scene_dependencies | List all resources a scene depends on |

Validation: validate

Validate before attaching or running. Catches syntax errors and missing resource references before they cause headless crashes or runtime failures. Supports scriptPath, source (inline GDScript), scenePath, or a targets array for batch validation.

UIDs: manage_uids (Godot 4.4+)

| Operation | Description | | --------- | --------------------------------------------- | | get | Get a resource's UID | | update | Resave all resources to update UID references |

Architecture

` src/ ├── index.ts # MCP server entry point, routes tool calls ├── tools/ │ ├── project-tools.ts # Project, runtime, autoload, filesystem, search, settings │ ├── scene-tools.ts # Scene creation, node addition, sprite loading, batch ops, UIDs │ ├── node-tools.ts # Node properties, scripts, tree, duplication, signals │ └── validate-tools.ts # GDScript and scene validation ├── scripts/ │ ├── godot_operations.gd # Headless GDScript operations │ └── mcp_bridge.gd # UDP autoload for runtime communication └── utils/ └── godot-runner.ts # Process spawning, output parsing, shared validation helpers ` Headless operations spawn Godot with --headless --script godot_operations.gd, perform the operation, and return JSON. Runtime operations communicate over UDP with the injected McpBridge autoload.

How the Bridge Works

When run_project or attach_project is called: 1. mcp_bridge.gd is copied into the project directory 2. It's registered as an autoload in project.godot 3. Godot launches with the bridge listening on 127.0.0.1:9900. With run_project, MCP spawns the process; with attach_project, you launch it yourself. 4. Runtime tools send JSON commands to the bridge and await responses 5. stop_project or detach_project removes the bridge script and autoload entry Files generated during runtime (screenshots, executed scripts) are stored in .mcp/ inside the project directory. This directory is automatically added to .gitignore and has a .gdignore` so Godot won't import it.

Acknowledgments

Built on the foundation laid by Coding-Solo/godot-mcp for headless Godot operations. Developed with Claude Code.

License

MIT