The honest summary
UE 5.0 to 5.8 is a source-compatibility target: the plugin guards engine APIs that differ across that range, and a compile failure on any of those versions is treated as a bug. That is not the same as every version having been tested live. The project's own evidence page says so directly: its recorded end-to-end certification run (20 of 20 stages passing on both the native and stdio routes) is on UE 5.7.4, and that record predates the current code. Day-to-day testing happens on the newest engines.
Build fixes for the oldest and newest engines landed during the 0.6 betas, listed per version below. If the plugin fails to compile on your version, open an issue with the engine version and the first errors from the build log.
Version notes
| Engine | Documented notes (from the changelog and issues) |
|---|---|
| 5.0 and 5.1 | Sequencer code used track functions that exist only from 5.2; 0.6.0-beta-c switched to the right names on every version, so the plugin compiles on 5.0 and 5.1. The ScaleByDeltaTime input modifier is refused before 5.1. |
| 5.0 to 5.4 | Issue #492 (verified on 5.3.2) found newer-engine APIs used without guards; fixed for 0.6 (#493). 0.6.0-beta-d notes the plugin "compiles again on UE 5.0-5.4". |
| 5.3 | Packed Level Actor baking (create_packed_level_actor) needs 5.3 or later; private data layers are refused before 5.3. |
| 5.4 | Rounded bevels in geometry tools are refused before 5.4; the SmoothDelta input modifier needs 5.4. |
| 5.5 | Skinning needs the Geometry Scripting plugin on 5.5 or later. |
| 5.6 | IK Rig creation needs 5.6 or later. Each capability answers with a clear message where its engine support is missing. |
| 5.7 | 0.5.30 failed to build on 5.7.4 (#542, closed; the IsStructureValid fix is #562). 5.7.4 is the engine with the recorded live certification. A report of a 5.7.1 build failure, #291, is still open. |
| 5.8 | Two engine API changes (FJsonObject::Values key type and UUserDefinedEnum::SetEnums) broke the build; the 0.6 betas fix both (#574 for the key type, an MCP_SET_ENUMS shim for the enum call) plus two more 5.8 build issues (#648). Issue #566 about SetEnums is still open on GitHub. On 5.8 only, EngineWire can also call Epic's editor toolsets through its gateway. |
A capability that needs an engine plugin you haven't enabled returns an error and everything else keeps working; search and describe list required plugins under availability.requiredPlugins. PCG support is compiled in only when the project itself enables the PCG plugin.
Blueprint-only projects: build binaries once
The release archives contain source only, so a project needs to compile C++. Two ways around that for Blueprint-only projects:
Add a C++ class. Tools › New C++ Class converts the project; Unreal then builds the plugin on open.
Build prebuilt binaries on one machine and share them. On a machine with the engine and a compiler, from a clone of the repository:
node scripts/package-plugin.mjs "C:/Program Files/Epic Games/UE_5.7"The script runs RunUAT BuildPlugin and writes build/McpAutomationBridge-v<version>-UE5.7-<Platform>.zip plus a SHA-256 manifest. Unzip it into YourProject/Plugins/ on each target machine; no compiler is needed there. On Windows, if RunUAT trips over long paths, point MCP_PACKAGE_STAGING_ROOT at a short folder such as X:\t.
A build only loads in the engine minor and platform it was built for. A 5.7 Win64 build won't load in 5.6, in 5.8, or on macOS. Build once per engine minor and platform your team uses.
Keep the server and plugin in step
On the stdio route, the npm package and the plugin must come from the same release, for example [email protected] with plugin 0.6.0-beta-e. The plugin's version is shown in Edit › Plugins and in McpAutomationBridge.uplugin (VersionName). The native HTTP route has no second component to keep in step.
The engine version and the EngineWire version are independent: the same 0.6 plugin source targets 5.0 through 5.8.
FAQ
Does EngineWire support UE 4?
No. The target range is Unreal Engine 5.0 to 5.8.
I see "modules are missing or built with a different engine version".
Unreal is asking to compile the plugin for your engine. Answer Yes; if it can't compile at runtime, build the Editor target in your IDE. Binaries copied from another engine version will not load. See troubleshooting.
Which version should I use for UE 5.8?
The 0.6 betas, which carry the 5.8 build fixes. Epic's own Unreal MCP is also available on 5.8; see the comparison.
Does it support macOS and Linux?
Yes, alongside Windows (Win64), with Xcode or clang as the compiler.