git:20260818.b1cefdd to git:20260907.4a1e3c8

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name: blender-character-workflow

description: Create, repair, rig, skin, animate, and export Blender characters, creatures, avatars, and facial rigs with deformation and runtime validation. Use when a request involves a character mesh, armature, weights, IK/FK, blend shapes, facial animation, humanoid/VRM/game export, or deformation quality.

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# Blender Character Workflow

Character completion requires deformation evidence. A mesh plus an armature is

not a finished rig.

## Establish the character contract

Record intended platform and export format, body/face scope, scale and axis,

triangle/material/texture budgets, bone naming and hierarchy requirements,

required controls, facial shape keys, poses/actions, and engine/avatar

constraints. Identify the minimum acceptance poses: neutral, extreme bend for

each major joint, reach, twist, locomotion/contact, and any required facial

expression.

## Build and rig deliberately

1. Keep the authored mesh, armature, controls, deformation helpers, and export

mesh in named collections. Apply or deliberately preserve transforms before

skinning; document the choice.

2. Create anatomically or mechanically plausible joint placement and semantic

bone names. Separate deform bones from animator controls where the target

benefits from it.

3. Keep symmetry and mirror workflows explicit. Limit vertex influences and

normalize weights according to the target runtime requirements.

4. Add IK/FK, constraints, corrective shapes, or drivers only when they solve a

named deformation need. Test without relying on a single flattering pose.

5. For facial work, name shape keys semantically and test combinations that

reveal volume loss, collisions, or eyelid/mouth failures.

## Validate export and motion

1. Render the neutral and every contract pose from front, profile, back, and

close-up deformation views. Open the evidence.

2. Check volume preservation, joint collapse, candy-wrapper twisting, clipping,

foot/hand contact, constraint cycles, control readability, and unwanted

scale/shear.

3. Export to the requested format, fresh-import it in a clean Blender process,

and compare armature hierarchy, skin weights where supported, materials,

actions, frame ranges, scale, and orientation.

4. Use `$blender-agent-studio:blender-animation-workflow` for action timing and

`$blender-agent-studio:blender-asset-validation` for authored/exported

geometry and hierarchy evidence.

## Fit modular VRChat hair

For arbitrary head and hair assets, use `scripts/fit_vrchat_hair.py`. It fits

the largest semantic hair mesh against the upper cranial region in evaluated

world space while applying one uniform transform to the complete hair rig.

Do not align the full hairstyle minimum Z to the head top; hanging strands and

ponytails make that measurement invalid.

Require a 1-8 mm median fitted clearance, no more than 15 mm p95 clearance,

fewer than 2% large gaps over 20 mm, and a 1.02-1.10 hair-to-cranium width

ratio. Preserve hair armatures, bones, weights, materials, UVs, and separately

named style meshes. Treat nearest-normal sign as a warning on multi-component

or open head meshes, not proof of penetration; confirm intersections in fixed

front, back, side, top, and perspective evidence. A Blender style visibility

setup is not proof that Unity/VRChat expression-menu toggles were authored.

## Completion gate

Deliver the editable source, export, bone/control map, tested pose/action list,

and fresh-import evidence. State any target-specific validation that could not

be performed in Blender; a successful GLB import is not proof of runtime avatar

compatibility.