Unreal Engine API Documentation — Claude Code MCP server
Provides AI agents with exact Unreal Engine C++ signatures, #include locations, and deprecation details without installing the engine.
claude mcp add --env UNREAL_VERSION=<UNREAL_VERSION> --env UNREAL_PROJECT_PATH=<UNREAL_PROJECT_PATH> --transport stdio unreal-engine-api-documentation -- uvx unreal-api-mcpWhat Unreal Engine API Documentation does
The server queries a local SQLite database compiled for specific engine releases. It determines the target version from the UNREAL_VERSION environment variable or the EngineAssociation property inside a .uproject file via UNREAL_PROJECT_PATH. UE 5.7 serves as the fallback whenever neither setting is passed. On its initial run, the tool fetches the database archive into ~/.unreal-api-mcp/.
Five tools handle agent queries. They cover keyword searches with search_unreal_api, parameter lookup via get_function_signature, header resolution through get_include_path, class structure via get_class_reference, and deprecation status in get_deprecation_warnings. The index contains Runtime, Editor, Developer modules, and built-in plugins such as Niagara or Gameplay Abilities.
Third-party plugins and marketplace assets are omitted entirely from the database. For non-stock extensions, the agent must inspect local project files instead. Running the server requires Python 3.10 and uvx, though having Unreal Engine installed locally is unnecessary.
What it helps with
- locate the correct
#includeheader for any engine class - verify C++ function signatures and argument types
- identify deprecated Unreal Engine methods and their replacements
- inspect Blueprint graph internal classes and K2 nodes
Example prompts for the agent
- Look up the exact
#includepath and method signature for AActor::GetActorLocation. - Check if K2_AttachRootComponentTo is deprecated and show what replaces it.
- Search the Unreal API for character movement classes and their headers.
How to install Unreal Engine API Documentation
Platform CLI
claude mcp add --env UNREAL_VERSION=<UNREAL_VERSION> --env UNREAL_PROJECT_PATH=<UNREAL_PROJECT_PATH> --transport stdio unreal-engine-api-documentation -- uvx unreal-api-mcpReplace <…> with your own values. uvx runs the command named after the package; if the README names another one, use uvx --from unreal-api-mcp <command>
Platform CLI
codex mcp add unreal-engine-api-documentation --env UNREAL_VERSION=<UNREAL_VERSION> --env UNREAL_PROJECT_PATH=<UNREAL_PROJECT_PATH> -- uvx unreal-api-mcpReplace <…> with your own values. uvx runs the command named after the package; if the README names another one, use uvx --from unreal-api-mcp <command>
Config file
{
"mcpServers": {
"unreal-engine-api-documentation": {
"command": "uvx",
"args": [
"unreal-api-mcp"
],
"env": {
"UNREAL_VERSION": "<UNREAL_VERSION>",
"UNREAL_PROJECT_PATH": "<UNREAL_PROJECT_PATH>"
}
}
}
}Replace <…> with your own values. uvx runs the command named after the package; if the README names another one, use uvx --from unreal-api-mcp <command>
Config file
{
"servers": {
"unreal-engine-api-documentation": {
"type": "stdio",
"command": "uvx",
"args": [
"unreal-api-mcp"
],
"env": {
"UNREAL_VERSION": "<UNREAL_VERSION>",
"UNREAL_PROJECT_PATH": "<UNREAL_PROJECT_PATH>"
}
}
}
}Replace <…> with your own values. uvx runs the command named after the package; if the README names another one, use uvx --from unreal-api-mcp <command>
Platform CLI
gemini mcp add -e UNREAL_VERSION=<UNREAL_VERSION> -e UNREAL_PROJECT_PATH=<UNREAL_PROJECT_PATH> unreal-engine-api-documentation uvx unreal-api-mcpReplace <…> with your own values. uvx runs the command named after the package; if the README names another one, use uvx --from unreal-api-mcp <command>
Step by step, with commands for each platform: How to add an MCP server to Claude Code, Codex, Cursor, VS Code, Gemini CLI and more
Questions about Unreal Engine API Documentation
How do I install Unreal Engine API Documentation in Claude Code?
Run `claude mcp add --env UNREAL_VERSION=<UNREAL_VERSION> --env UNREAL_PROJECT_PATH=<UNREAL_PROJECT_PATH> --transport stdio unreal-engine-api-documentation -- uvx unreal-api-mcp. For a quick start without explicit variables, use claude mcp add unreal-api-mcp -- uvx unreal-api-mcp`.
What does Unreal Engine API Documentation do?
It provides coding assistants with verified C++ declarations, headers, and obsolescence notices from engine code. This prevents the model from hallucinating non-existent parameters or missing includes.
Do I need Unreal Engine installed locally to use this server?
Local engine files are not required. The server downloads self-contained SQLite archives directly to ~/.unreal-api-mcp/ on first launch.
