Ralpha for Unreal Engine
Unreal Engine 5.8 ships its own MCP server. Ralpha plugs into it as toolsets and skills: real places, sun and exposure that are calculated rather than guessed, and the rules we measured building production scenes.
Version 1.3.1 for Unreal Engine 5.8 (tested on 5.8.3) · $99 personal / $299 professional
Platforms
Win64, Mac (Apple silicon) and Linux. Win64 and Mac are built from the release archive, installed cold into a new project and live-tested. Linux builds from the same archive but has not yet been live-tested by us.
Intel Macs are not supported.
What you get
- Geo toolset for Cesium for Unreal 2.x: latitude/longitude camera placement, georeference, tilesets and terrain height (Cesium installed separately)
- Solver toolset: sun position for any place and time, exposure from sun elevation, lens field of view, horizon distance, sea state and stars
- Six domain skills registered with Unreal’s agent-skill system: sky and sun, sunset, water and ocean, clouds, exposure, and real places
- Water and ocean spawning and wave control, with no blocking dialogs
- Photoreal MetaHuman support
- MuJoCo 3.3.2 runtime: load a model, step it, bind bodies to actors, read state
- Commands that cannot do what you asked say so, with the reason, instead of reporting success
- Localhost only; outbound network off by default; no telemetry
- Full C++ and Python source. No content: the package contains no characters, maps or meshes
3,248 commands register in UE 5.8; 3,176 were verified one by one in a fresh project, each with its effect read back. The other 72 need particular hardware, a platform, or a paid service or device.
Getting connected
- 1
Install from Fab into your project
When the listing is live, add the plugin to a UE 5.8 project from Fab. Docs/INSTALLATION.md in the package lists the engine plugins to enable.
- 2
Start Unreal’s own MCP server
Enable Unreal’s MCP plugins and start the editor with -ModelContextProtocolStartServer -ModelContextProtocolPort=30030. Ralpha registers its toolsets and skills with it at startup.
- 3
Point your MCP client at the editor
Use http://127.0.0.1:30030/mcp from Claude Code, Epic’s AI Assistant or any other MCP client. The plugin also serves HTTP MCP on 30020 and TCP/JSON on 30010 as a secondary path.
Known limits
We test every command and publish what we found.
- Hardware or platform (50) nDisplay is not available on Mac, because UE 5.8 ships nDisplay only for Windows and Linux (on Windows all 46 nDisplay commands passed). Path tracing and VDB volume import need hardware ray tracing (verified on Windows with an RTX 4070). Hand tracking needs an XR device. Vehicle commands need a Chaos wheeled vehicle you supply.
- Paid services, licences or devices we have not tested with (22) For example Wwise audio, Meshy mesh generation, VR headsets, OSC tally devices and multi-node nDisplay clusters. They stay in the package and are listed in Docs/COMMAND_REFERENCE.md.
- Some Mac Development builds can fail to launch intermittently; a stock UE 5.8 project shows the same. Docs/TROUBLESHOOTING.md has the measured rates and the -LLM launch option (0 failures in 150 launches with it).
- Linux builds from the release archive but has not been live-tested by us.
- Editor workflow. The native toolsets and skills need the editor running.
Ralpha Brain (coming)
An optional companion app, downloaded separately from this site once it is published. Free for the first 30 days with no card, then $19.99 a month. It runs on your own Claude subscription; no model is included. The plugin works without it.
The plugin will be licensed to you through Fab, under the Fab licence tier you buy (Personal or Professional).
Product overview · Version notes · Pricing · support@ralpha.io