About Coating Lab
Coating Lab is an MCP server for game-weapon artists who need sourced material finishes and wear baked into Blender models. It supports finish variants, validation, renders, and engine-ready material values using a shared wear formula.
Key features
- 01Sourced physically based finish library
- 02Per-slot finish variants and wear levels
- 03Bake evidence-based wear masks in Blender
- 04Validate finishes and coating specs
- 05Render variants and export engine values
Use cases
- 01Apply varied finishes to weapon model slots
- 02Bake wear patterns into vertex colours
- 03Check coating variants against wear rules
MCP support
Exposes finish lookup, coating-spec validation, wear baking, rendering, and engine-parameter tools to MCP clients.
Configuration
Local server config is the same for every client. Copy it into your client’s MCP config file.
uvx coatinglab-mcpCOATINGLAB_OUTThe only folder Coating Lab writes to; defaults to ~/.coatinglabCOATINGLAB_BLENDERBlender's executable, if it is not on the PATH or in the usual install folderCOATINGLAB_LIBRARYA finishes JSON of your own, merged over the built-in libraryCOATINGLAB_WAIT_FORProcess names that hold the machine (e.g. UnrealEditor.exe); a bake refuses to start while one runsLocal servers need a runtime on your machine (e.g. Node.js 18+). Config file locations differ by client; see your client’s docs.
Tools
13Saved tool list · updated 2w ago
This tool takes no parameters.
Details
From the project READMECoating Lab
Real surface finishes for game gun models, worn where use wears a gun.
An MCP server that gives game gun models real surface finishes, worn where use wears a gun.
- A finish library with sources. Anodized aluminium, manganese and zinc phosphate, blued and nitrided steel, ceramic coatings (FDE, OD green, tungsten, graphite, coyote), stainless, polymer, rubber, brass, copper, lead, walnut. Each is a physically based value (linear colour, metallic, roughness) with what shows when it wears through and the sources of its numbers. Values reasoned from descriptions are marked as estimates.
- Coating variants. A spec puts a finish on each material slot of a model, in as many variants as you want (an issued rifle, a two-tone FDE build, an abused one), each at a wear level: new, issued, worn or abused.
- Wear from evidence, baked once. In Blender, into the model's vertex colours: exposed edges, where the hands work the gun (its grip, the support hand, the controls), where parts slide (a magazine in its well, a stock on its tube), and dirt where the surface is occluded and round the muzzle and the port. Every variant reads the same masks, so a new variant costs nothing.
- Checks. Every finish against the rules physically based rendering rests on. Every variant's worn share against its level, and no wear inside corners.
- One formula everywhere. The checks, the look-dev renders and an engine's material compute wear the same way
(
coat.py), so what passes is what the player sees.

Model Lab (modellab-mcp) builds give their own slots (upper, lower,
barrel and more), marks and parts: spec_for_modellab makes a coating spec from a build in one call.
Install
Python 3.10 or later and Blender 4.2 or later.
pip install coatinglab-mcp
{"mcpServers": {"coatinglab": {"command": "coatinglab-mcp"}}}
| Setting | Meaning |
|---|---|
COATINGLAB_OUT | The only folder Coating Lab writes to. ~/.coatinglab by default. |
COATINGLAB_BLENDER | Blender, when it is not on the PATH or in the usual install folder. |
COATINGLAB_LIBRARY | A finishes JSON of your own, merged over the built-in library. |
COATINGLAB_WAIT_FOR | Process names that hold the machine. A bake waits for none of them to run. |
Tools
| Tool | What it does |
|---|---|
list_finishes, read_finish | The library, and one finish with its notes and sources. |
check_library, check_finish | The library, or a finish of your own, against the physical rules. |
list_wear_levels, list_templates | The wear levels, and the ready variant sets. |
spec_for_modellab | A coating spec for a Model Lab build. |
validate_spec | A spec's problems: a slot without a finish, a finish on the wrong material. |
bake | Bakes the wear masks into a copy of the model. |
check_coating | Each variant's wear against its level, and wear kept out of corners. |
render_variants | Look-dev renders and a sheet. |
engine_params | A variant's values by slot for an engine material. |
The masks and the formula
The bake writes the vertex colour Col:
| Channel | Meaning |
|---|---|
| R | Edge: 1 on flat ground, 0 on a sharp exposed edge |
| G | Handling: 1 where the hands work the gun |
| B | Rub: 1 along the lines parts slide on |
| A | Dirt: 1 where the surface is occluded, and round the muzzle and the port |
An engine's material follows the formula in src/coatinglab/coat.py. A wear level is a threshold: the higher the
level, the weaker the mask that already wears through. A grunge texture breaks wear up but never makes wear.
What is estimated
- Every roughness value. No source maps a finish's surface to a rendering roughness.
- The colours of the anodized, phosphate, blued, nitrided and most ceramic finishes. The standards set processes, not colours. OD green and coyote come from FED-STD-595 colour numbers.
- The wear amounts. Sources say where guns wear, not how fast. Each level is set so Model Lab's M4A1 lands in the middle of its band.
- A hand's zone is a sphere: on a round handguard the support hand's wear reaches its top as well as its underside.
License
MIT
Comments
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