version: "1.0.0" name: houdini-materials description: >- Authoring skill - create and assign Houdini materials, including typed MaterialX PBR networks for Karma. Use when building lookdev/material workflows from color, roughness, metallic, normal, or displacement maps. Not for generic node graph edits. license: MIT compatibility: "meshy-dcc-houdini 0.1+, Houdini 18.5+, meshy-dcc-core 0.2.0+" allowed-tools: Bash Read Write Edit metadata: meshy-dcc: dcc: houdini layer: domain stage: authoring version: "1.0.0" tags: [houdini, materials, lookdev, shader, materialx, pbr, karma, displacement, assignment, authoring] search-hint: "create material, assign material, MaterialX PBR, Karma shader, texture maps, normal, displacement, lookdev" search-aliases: [create material, make shader, add material, assign material, set material, principled shader, materialx standard surface, pbr textures, karma material, normal map, displacement map, apply material to object] example-prompts:

• "Create a red principled shader and assign it to /obj/geo1"
• "Build a Karma MaterialX PBR material from color, roughness, normal, and displacement textures"
• "Validate that /mat/planet has its MaterialX PBR channels connected"
• "Make a new material in /mat"
• "Assign the clay material to the selected object"

intent: "Create Houdini material/shader nodes and assign them to renderable nodes." recall-context: app_type: houdini domain: lookdev workflow-stage: authoring task-category: mutate requires: [] produces: [scene_node, material] preconditions:

• type: software

name: houdini version: ">=18.5" side-effects: creates: true modifies: true targets: [scene_node, material] tools: tools.yaml

houdini-materials

Authoring an arbitrary MaterialX graph

build_materialx_pbr produces a fixed standard-surface material. To go beyond that preset, add nodes into the MaterialX subnetwork and wire them with the existing lookdev tools:

1. create_materialx_node(material_path="/mat/materialx_pbr", node_type="mtlximage")
2. houdini_lookdev__connect_shader(node_path=..., source_path=...) to wire the

node into the surface graph

1. inspect_materialx_graph(material_path="/mat/materialx_pbr") to read back the

node inventory, the input wiring and any node that is still unwired

1. validate_materialx_pbr(material_path=...) to confirm the material still

compiles for Karma

inspect_materialx_graph inspects structure only: it reports validation_scope="graph_structure" and compiled=false, because reading a node list does not tell you whether the material renders.

Typed material authoring for Houdini scenes. Use create_material for material network nodes and assign_material for renderable OBJ/SOP nodes with a material path parameter. Use build_materialx_pbr for a complete MaterialX Builder with standard-surface, normal-map, and displacement outputs, then call validate_materialx_pbr before assignment or rendering.

build_materialx_pbr treats base color as color data and roughness, metallic, normal, and displacement as raw data by default. It removes the newly created subnet if any node or connection fails; it never replaces an existing material.