qFoldIT Toolbelt — Unity

109 composite editor-automation tools for Unity, exposed to AI agents through Unity's own official MCP bridge.

Built by qFoldIT — foundation release, 2026

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What this is

Unity 2023+ ships its own MCP server built into the Editor (com.unity.ai.assistant, "Unity MCP"). It already gives an AI agent a generic, low-level surface: run C#, query the scene, call arbitrary editor APIs. qFoldIT Toolbelt does not replace that — it registers a second layer of higher-level, composite tools on top of it, the same way UEFN Toolbelt built 355 named commands on top of UEFN's raw Python API instead of making an agent write one-off scripts every time.

Instead of an agent writing:

// 15 lines of GameObject.CreatePrimitive + loop math + material setup
// to place 12 crates in a circle with a neon material...

it calls:

procedural_place(pattern="circle", count=12, radius=5)
material_bulk_swap(name_contains="Crate", preset="neon")

Architecture

Claude / any MCP client
    │  MCP protocol (stdio, via Unity's relay binary)
    ▼
Unity Editor  ──  McpToolRegistry (built into com.unity.ai.assistant)
    │
    ▼
qFoldIT Toolbelt tools  (Editor/Tools/*.cs, [McpTool] attributes)
    │
    ▼
UnityEditor / UnityEngine APIs

No external process, no HTTP relay, no polling — this package is pure C# that Unity's own TypeCache scan discovers at Editor startup, exactly as documented in Register custom MCP tools.

See ARCHITECTURE.md for the full design and docs/TOOL_REFERENCE.md for every tool's signature.

Install

1. Ensure com.unity.ai.assistant (Unity MCP) is installed and enabled: Edit → Project Settings → AI → Unity MCP.
2. Add this package via Package Manager → "Install package from disk" and point it at this folder's package.json, or add it to Packages/manifest.json:

   "com.qfoldit.toolbelt": "file:../qfoldit-unity-toolbelt"

3. Reopen the Editor. The tools appear automatically under AI → Unity MCP → Tools and are exposed to any connected MCP client (Claude Code, Cursor, etc.) — no separate server to start.
4. Optional: qFoldIT → Toolbelt → Export Tool Manifest writes Saved/QFoldIT_Toolbelt/tool_manifest.json for agents that prefer to load a static manifest instead of calling MCP's live list tools.

Tool categories (109 tools total)

Category	Tools	What it covers
Animation	5	Create AnimatorControllers, states, transitions, parameters, and attach them to objects.
Assets	3	List, instantiate, and find project assets by type and name.
Audio	5	AudioSource setup, one-shot playback, mixer groups, listener management, reverb zones.
Camera	5	Create cameras, dependency-free follow behaviour, clipping planes, background, screenshots.
CodeGen	1	Generates a MonoBehaviour with real, bindable public fields for named scene objects.
Components	5	Reflection-based generic add/remove/get/set/list for any component type.
BuildConsole	3	Execute menu items, trigger player builds, read console log entry count.
Interaction	2	Real interaction realization: attaches a working, pre-compiled QFoldITInteractable component (click-wired UnityEvent) for any of the 10 gameplay mechanics or legacy triggers.
Lighting	6	Create lights, set skybox/ambient/fog, bake lightmaps, apply full lighting presets.
Materials	4	12 material presets, bulk swap by name match, team-color split, preset listing.
Measurement	3	Distance between objects, per-object bounds, and full-scene bounds.
Navigation	4	Bake NavMesh, add agents/obstacles, set runtime pathing destinations.
Particles	4	7 particle system presets (fire, smoke, explosion, sparkle, rain, snow, magic) plus fine control.
Physics	6	Rigidbody/collider setup, physics materials, joints, raycasts, global gravity.
PostProcessing	5	URP Volume/VolumeProfile setup: bloom, vignette, color adjustments, depth of field.
Assets	4	Create prefabs from scene objects, apply/revert overrides, unpack instances.
Procedural	2	8 geometric placement patterns (grid, circle, arc, spiral, line, wave, helix, radial) plus a symmetrical arena generator.
Project	1	Standard folder scaffold plus a boilerplate GameManager singleton MonoBehaviour.
SceneManagement	5	Create, load, unload, activate, and save scenes in a multi-scene setup.
Scene	8	Spawn, transform, clone, delete, parent, list, and find GameObjects in the active scene.
ScientificVisualization	2	Real scientific-state visualization: mechanic-differentiated visible anchors with optional world-space labels, plus QFoldITScientificBinding components for live scientific-state URIs.
Stamps	3	Save a selection as a reusable stamp; place it anywhere with rotation; list saved stamps.
TagsLayers	4	Create and assign tags and layers, including recursive layer assignment.
Terrain	5	Create terrain, sculpt hills/craters, flatten, paint textures, scatter trees.
UAGBridge	2	Validates and realizes qFoldIT Universal Assembly Graphs by calling this toolbelt's own tools — the Universal World Interface adapter connecting Unity to the rest of the qFoldIT stack.
UI	7	Build uGUI Canvas hierarchies: buttons, text, panels, sliders, images, anchor presets.
Utility	4	Batch rename, Game view screenshots, Editor undo/redo.
WorldState	1	Exports the full scene graph (names, components, transforms, parents) to JSON for AI context.

Roadmap to parity

This release brings the toolbelt to 109 real tools across 28 categories — still short of UEFN Toolbelt's 355, but well past the 25-tool foundation. More importantly, this revision adapts the whole UAG Bridge to qfoldit-engine-adapter-spec-v0.1, the formal spec package (not the earlier informal Phase-1 draft): UagModel.cs now matches the normative schemas/uag.schema.json exactly (schema/scene/ node.parent/bindings[]), uag_validate emits {code, message} errors matching the spec's own conformance/test_vectors.json byte-for-byte, and qfoldit.adapter.json (this repo's root) is strictly valid against schemas/adapter-manifest.schema.json.

Real, verified milestone: running the spec's own unmodified reference/compiler.py (from qfoldit-scientific-gameplay-framework-v0.1) against this repo's actual qfoldit.adapter.json now compiles all 5 currently-unlocked gameplay patterns with status=success and zero gaps — up from 0/5 before this revision (see cross-engine-compile-report.md in that package). This was earned by building real capability, not by editing the manifest's status field by hand:

• interaction (blocked 4/5 patterns): Runtime/QFoldITInteractable.cs — a real, pre-compiled MonoBehaviour in a dedicated Runtime assembly (works in Play Mode and builds, not just the Editor) with a working OnMouseDown → UnityEvent wiring, for all 10 gameplay mechanics plus legacy triggers. interaction_create attaches it to any node.
• scientific.visualization (blocked 5/5 patterns): ScientificVisualizationTools.cs realizes every UAG scientific_subject/<mechanic> node as a real, visible, mechanic-differentiated object (shape + material preset keyed by mechanic), with Runtime/QFoldITScientificBinding.cs giving bindings[] genuine, queryable substance instead of accepting-and-discarding a scientific-state:// URI.
• geometry.procedural (blocked 2/5 patterns): already real, working capability from an earlier revision (procedural_place's 8 patterns + arena_generate) — the manifest's earlier "partial" rating undercounted it; no new code was needed, just an honest status correction.

See docs/UAG_BRIDGE.md for the full contract, mapping table, and — importantly — what these capabilities honestly do not cover (native per-mechanic gameplay logic, live Niagara-style parameter-mapped feedback). tests/conformance/ runs the spec's real test_vectors.json against the actual, unmodified UagValidator.cs.

Structured to keep growing the same way: new files under Editor/Tools/, each adding [McpTool] methods, tracked in registry.json.

License

AGPL-3.0, with an additional visible-attribution requirement — see LICENSE. Any tool built on this codebase must credit qFoldIT and link back to this repository (see LICENSE for the exact wording); network/hosted use requires publishing your modified source.