UE5 GamesOS MCP

A Practical Note from the Overnight Build System

Last night, while running the UE5 GamesOS build with MCP, I noticed a few things that could be crucial for anyone in the thick of Unreal Engine 5 production. The overnight run, especially when integrating the UI Automation Harness (Track-A watchdog scaffold), highlighted several specifics worth addressing.

UI Automation Harness

The UI Automation Harness, or Track-A watchdog scaffold, is pivotal in monitoring the build process. During the overnight run, it caught two key discrepancies in our .uproject setup. The first was a missing mcp.json configuration file, which halted the MCP plugin from auto-starting. This is a critical step outlined under the "UE5 Readiness Gate" section of our local ENGINE_MCP_PRODUCTION_STANDARD.md document, stored at D:\TE-Code\ProductOS\GamesOS\docs.

Readiness and Configuration

Before initiating any build, the "UE5 Readiness Gate" checklist demands that the Unreal version and .uproject path be confirmed. This prevents common startup errors. In our case, a misconfigured Git state led to a dirty working directory—something the readiness gate is designed to catch. The .uproject path was set correctly, but the missing mcp.json was a hiccup that prevented the MCP client-specific config from loading, as detailed in our GamesOS/CLAUDE.md.

MCP and Plugin Verification

The importance of verifying the MCP plugin and any companion plugins like Vibe UE or Web UE cannot be overstated. The overnight run revealed that the Vibe UE plugin was not installed, conflicting with our local documentation that listed it as a requirement. This underscored the need for regular checks against references/source-notes.md to ensure all plugins are up-to-date and installed.

Importance of Evidence

Finally, capturing evidence through screenshots or videos is non-negotiable. The overnight run reminded me of this when the capture script failed to execute due to an incorrect path setting in our PIE configuration. This is a part of the "Production Loop" where every change must be proven with evidence, as emphasized in the GAMESOS_ASSET_CREATION_FLOW.md.

Conclusion

The overnight build system, with its focus on UI Automation Harness and MCP readiness, serves as a practical reminder of the intricacies involved in UE5 production. From ensuring plugin installations to configuring MCP correctly, each step is integral and backed by specific documentation pathways. The evidence captured—or the lack thereof—ultimately dictates the success of our builds. Keep your documentation close and your configurations closer.