verse-diagnostics-mcp

MCP server that parses UEFN Verse build diagnostics from UnrealEditorFortnite.log and exposes structured error data to Claude Code, Cursor, VS Code, or any MCP client.

Tools

Quick Start

Claude Code (uvx — recommended)

claude mcp add-json verse-diagnostics '{
  "type": "stdio",
  "command": "uvx",
  "args": ["verse-diagnostics-mcp"],
  "env": {
    "UEFN_LOG_PATH": "/mnt/c/Users/YOUR_USER/AppData/Local/UnrealEditorFortnite/Saved/Logs/UnrealEditorFortnite.log",
    "VERSE_PROJECT_ROOT": "C:/Users/YOUR_USER/Documents/Fortnite Projects"
  }
}' --scope user

Claude Desktop / Cursor / VS Code

Add to your MCP config (claude_desktop_config.json, .cursor/mcp.json, etc.):

{
  "mcpServers": {
    "verse-diagnostics": {
      "command": "uvx",
      "args": ["verse-diagnostics-mcp"],
      "env": {
        "UEFN_LOG_PATH": "C:\\Users\\YOUR_USER\\AppData\\Local\\UnrealEditorFortnite\\Saved\\Logs\\UnrealEditorFortnite.log",
        "VERSE_PROJECT_ROOT": "C:\\Users\\YOUR_USER\\Documents\\Fortnite Projects"
      }
    }
  }
}

pip install

pip install verse-diagnostics-mcp
verse-diagnostics-mcp

Environment Variables

Example Output

{
  "ok": false,
  "source": "uefn-log",
  "error_count": 3,
  "warning_count": 0,
  "diagnostics": [
    {
      "file": "Berry/Content/hello_world_device.verse",
      "line": 25,
      "column": 17,
      "endLine": 25,
      "endColumn": 31,
      "severity": "error",
      "code": "VRS3506",
      "message": "Unknown identifier `switch_manager`",
      "timestamp": "2026-03-07T11:46:52+00:00"
    }
  ]
}

How It Works

The server reads UEFN's UnrealEditorFortnite.log and parses VerseBuild: lines using regex. It extracts file paths, line/column ranges, error codes, and messages, deduplicates them (UEFN sometimes logs the same error twice with slightly different formatting), and returns structured JSON.

This is a read-only log parser — it cannot trigger builds. The user must compile from UEFN or VS Code (verseWorkflow.compile), then this server reads the results.

CLAUDE.md Integration

Add this to your UEFN project's CLAUDE.md:

## Verse diagnostics workflow
- After modifying any `.verse` file, use `get_verse_diagnostics` to check for errors.
- If diagnostics include errors, fix them and recheck until `"ok": true`.
- If an API is unfamiliar, verify against official Verse documentation before using it.
- Success = `"ok": true` in diagnostics output.

License

MIT