190 curated tools across 37 domains, with a self-growing workflow intelligence layer that learns from every session. Give Claude full control over Blueprints, materials, levels, sequencer, AI, and more — on Unreal Engine 5.4 through 5.8.
Features
Built for real game development workflows — not just demos. Every failure mode has a recovery path.
13 typed UMA_E_* codes replace raw string errors. Every failure includes error code, tool name, and structured details for reliable programmatic handling.
Auto-disables tools after 5 consecutive failures. Self-heals after a 60-second cooldown. A ping command resets the circuit without a restart.
30-second default, up to 5 minutes for builds and long workflows. 16 long-running tools receive extended timeouts automatically — no configuration needed.
Parse errors trigger automatic fix-and-retry cycles. Up to 3 attempts before reporting to the developer — most compilation failures resolve without human intervention.
Destructive operations require explicit human approval via UE editor dialog. 60-second timeout with auto-reject on no response keeps your project safe.
Intent matching with 60+ UE synonym groups. Learns from workflow outcomes and error resolutions — gets smarter with every session.
New in v0.6.0
The knowledge base no longer waits for you to teach it. Every tool call now feeds a loop that observes, tracks, learns, and assists — automatically.
Every tool call is journaled server-side automatically, with zero extra calls required from the AI.
Workflow outcomes are recorded automatically once a high-confidence intent match completes its required steps.
context-suggestWorkflows mines the usage journal for frequent tool sequences and surfaces them as candidates the AI can formalize into new workflows — a self-growing knowledge base.
Tool results carry an opt-out _uma hint block: known-error fixes on failure, progress and next-step suggestions on success.
TF-IDF hybrid matching combined with 90-day time-decayed outcome confidence — recent successes weigh more than stale ones.
context-recommend and the new context-getUsageStats tool surface next-tool suggestions weighted by real usage, visible live on the analytics dashboard.
Positioning
Epic now ships a first-party MCP plugin in UE 5.8 (Experimental). Here's how the two compare — and why they aren't mutually exclusive.
| Dimension | Unreal Master Agent | Epic Unreal MCP (UE 5.8, Experimental) |
|---|---|---|
| Curated tools | 190 tools across 37 domains | Experimental toolset registry |
| Self-growing intelligence | Yes — 89 workflows, auto-learning, error-resolution memory | Not provided |
| UE versions | 5.4 – 5.8 | 5.8 only |
| MCP hosts / transport | All MCP hosts, incl. stdio — UE connects out over WebSocket | HTTP + SSE only |
| Self-healing compile loop | Yes — automatic fix-and-retry, up to 3 attempts | Not provided |
| Community workflow marketplace | Yes — importable workflow gallery | Not provided |
| Maturity | 1,336 tests, circuit breaker, safety gates | Experimental |
Epic shipping a first-party MCP plugin validates the category. Both can run side-by-side against the same UE instance — different ports and protocols, no conflict.
Architecture
A clean separation between AI reasoning, protocol bridging, engine interfacing, and API execution.
Layer 01
Interprets natural language, decides tool sequences, applies context intelligence for workflow matching and error recovery.
Layer 02
190 registered tools across 37 domains. Auto-registration architecture with domain index.ts modules, ToolHookManager, custom tool discovery, and extensible Python script support.
Layer 03
Blueprint graph serializer, Python bridge for 166 automation scripts, human approval gate for destructive operations, and Live Coding integration.
Layer 04
Direct C++ and Python API calls into the engine. All editor API calls dispatched via GameThread to satisfy UE's thread-safety requirements.
Tools
Every major Unreal Engine system exposed through a single natural language interface.
Changelog
Living Intelligence
New Living Intelligence layer: every tool call is auto-journaled, workflow outcomes are auto-recorded after high-confidence intent matches, and proactive _uma hints surface known-error fixes and next-step suggestions in tool results (opt out via UMA_HINTS=off). Sequence mining surfaces emerging workflow candidates for the AI to formalize into new workflows. Two new tools — context-suggestWorkflows and context-getUsageStats (190 total tools, 18 in the Context domain). Hybrid TF-IDF intent matching with 90-day time-decayed outcome confidence and usage-weighted next-tool recommendations. Analytics dashboard fixed and now shows live tool-usage stats. Declared support for Unreal Engine 5.8 following a full compatibility analysis (Windows source builds on 5.8 require Visual Studio 2026).
Extensibility
server.ts refactored from 1490 to 158 lines. Tool registrations moved to 37 domain index.ts modules via auto-registration. ToolHookManager for pre/post execution hooks. Custom tool discovery from custom-tools/ directory. Custom Python scripts via Content/Python/uma_custom/. Two new tools: python-customExecute and python-listCustomScripts (188 total tools, 1228 tests).
Security Hardening
WebSocket authentication via shared secret with crypto.timingSafeEqual. Sliding-window rate limiting wrapping all 183 tools. Enhanced path traversal prevention blocking null bytes, encoded traversals, and UNC paths. Asset path validation in safety gate. Input validation audit across all tools.
Observability
JSON structured logging with LOG_FORMAT env var and withContext(). OpenTelemetry-compatible tracing with W3C traceId/spanId and OTLP export. Performance dashboard with p50/p95/p99 latency percentiles. Error rate alerting via webhook with sliding window and cooldown.
Error Handling & Resilience
Introduced 13 typed UMA_E_* error codes replacing raw string errors. Added circuit breaker with 5-failure threshold and 60s cooldown. Extended timeouts for 16 long-running tools. Reconnection tracking.
Get Started
Unreal Master Agent runs as a local MCP server. No accounts, no cloud dependency. Add it to Claude Code's config and it activates immediately in your next session.
The UE plugin connects via WebSocket on port 9877. Once connected, Claude can read your entire project structure, manipulate Blueprints, spawn actors, edit materials, and run Python scripts — all through natural language.
.claude/mcp.json in your project or home directory
Plugins/ folder
{ "mcpServers": { "unreal-master": { "command": "npx", "args": [ "-y", "unreal-master-mcp-server" ], "env": { "UE_WS_PORT": "9877" } } } }