---
type: concept
topic: ue-mcp-strategy
status: active
created: 2026-06-16
updated: 2026-06-16
source_notes:
  - "[[research/ue-mcp-strategy/sources/interchange-and-lock-in]]"
derived_from:
  - web-research
confidence: medium
shared_concept:
---
# Runtime Gravity & Lock-In (what the moat actually is)

## What "Gravity" Mechanically Means for an Engine

"Gravity" is not one thing — it is a stack of switching costs, and they are not equally strong:

1. **Content lock-in (strongest).** Engine-native, non-portable artifacts: Verse code, Blueprint graphs, and tuning baked against UE-specific systems (Nanite, Lumen, the cook pipeline). These have *no export path* to Unity or Godot — you rewrite, not migrate. (FACT)
2. **Talent / labor lock-in.** A workforce trained on UE's editor, C++ reflection model, and Blueprints; re-skilling to another engine is real cost. (REASONING)
3. **Network effects.** Fab marketplace (assets bought *for* UE), tutorials, plugins, the UEFN creator economy — each new creator raises the value of staying. (REASONING)
4. **Standard-setting.** When UE becomes the default for virtual production / archviz, the ecosystem builds *toward* it. (REASONING)

Critically, Epic's value capture is contractually tied to layer 1: the royalty triggers only when a shipped product "relies on UE code **at runtime**." Gravity that does not touch the runtime is gravity Epic cannot bill. (FACT — see [[research/ue-mcp-strategy/sources/interchange-and-lock-in]] and [[research/ue-mcp-strategy/concepts/ue-value-capture-map]].)

## How AI Generation Amplifies (or Erodes) It

The bull mechanism: AI floods the ecosystem with UE-native content; volume of non-portable artifacts explodes; gravity compounds. This is *directionally true only for the non-portable surfaces* — Verse logic and Blueprint graphs an MCP emits genuinely deepen lock-in. (REASONING)

The erosion: most AI *asset* generators (Meshy, Scenario, Anything World) emit portable meshes/textures, not UE-native logic. If the AI wave is mostly assets, it pours into portable formats and barely moves gravity. The bull case lives or dies on the **ratio of non-portable logic to portable assets** in what the MCP emits — which is exactly why the workspace's "UE-advantaged, never engine-neutral" rule exists. See [[research/ue-mcp-strategy/concepts/ai-content-generation-frontier]].

## Interchange Standards That Cut the Other Way (USD/glTF)

OpenUSD (Pixar/Linux Foundation), glTF 2.0 (Khronos, royalty-free), and FBX move assets across engines; UE 5.4+ unified them under the Interchange framework. The decisive fact: **Epic is a founding member of the Alliance for OpenUSD — alongside Unity.** Epic is actively making the asset layer *more* portable. By its own actions, Epic appears to bet gravity on the runtime + UEFN economy, not on trapping assets. (FACT)

## Why It Matters for the MCP-vs-Harness Question

If gravity = non-portable runtime/logic content, an MCP that emits UE-advantaged Verse/Blueprints is accretive, and a harness adds little strategic moat. If gravity is actually thin (assets portable, Epic itself standardizing them), opening the MCP mostly helps *creators leave faster* once an engine-agnostic layer exists. The decision hinges on which layer the moat really sits in. See [[research/ue-mcp-strategy/concepts/harness-vs-mcp]] and [[research/ue-mcp-strategy/concepts/the-bear-case]].

## Critical Questions

- What % of a generated project's value is non-portable (Verse/Blueprint) vs portable (USD/glTF mesh)? That ratio *is* the moat.
- Does Epic's AOUSD membership concede the asset layer — making "content gravity" really "UEFN-economy gravity," owned by a different team?
- Can an MCP be *forced* to emit non-portable content, or will agents route around it to portable formats?

## Related Concepts

- [[research/ue-mcp-strategy/concepts/the-bear-case]]
- [[research/ue-mcp-strategy/concepts/ue-runtime-architecture]]
- [[research/ue-mcp-strategy/concepts/mcp-as-tooling-surface]]
- [[research/ue-mcp-strategy/concepts/harness-vs-mcp]]
- [[research/ue-mcp-strategy/concepts/ue-value-capture-map]]
- [[research/ue-mcp-strategy/concepts/ai-content-generation-frontier]]

## Sources

- [[research/ue-mcp-strategy/sources/interchange-and-lock-in]]
- UE licensing / runtime royalty test — https://www.unrealengine.com/license
- AOUSD (Epic + Unity as members) — https://nvidianews.nvidia.com/news/aousd-to-drive-open-standards-for-3d-content
- USD in Unreal Engine — https://dev.epicgames.com/documentation/unreal-engine/universal-scene-description-in-unreal-engine
- glTF 2.0 as standard — https://godotengine.org/article/we-should-all-use-gltf-20-export-3d-assets-game-engines/