Assign a material to a Houdini geometry node using a Material SOP by specifying the target geometry path and material path.
Assign a material to a geometry node via a Material SOP.
Args: geo_path: Target geometry node path. material_path: Material to assign.
| Name | Required | Description | Default |
|---|---|---|---|
| geo_path | Yes | ||
| material_path | Yes |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the operation ('Assign a material') but does not disclose side effects, such as whether the Material SOP is created/modified, whether existing material assignments are overwritten, or whether the scene is modified irreversibly. For a mutation tool with zero annotation coverage, this is a significant gap.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is compact and front-loaded with the main action, followed by a concise parameter list. It earns its place with no filler, though the parameter list is somewhat redundant with the schema.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a mutation tool with no annotations, no output schema, and 0% schema description coverage, the description is incomplete. It does not explain what happens after assignment, how to verify success, or what errors might occur. An agent would need to infer prerequisites and side effects from the tool name and sibling context.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 0%, so the description must compensate. It does add minimal meaning by naming the parameters ('geo_path: Target geometry node path', 'material_path: Material to assign'), which clarifies their roles beyond the bare schema titles. However, it does not explain expected path formats (e.g., '/obj/geo' vs relative paths) or whether the material path must point to a specific node type.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description states a specific verb ('Assign') and resource ('material to a geometry node via a Material SOP'), which clearly identifies the operation. It does not explicitly distinguish it from sibling tools like create_material or list_materials, but the action is specific enough that an agent can infer its purpose.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description provides no guidance on when to use this tool versus alternatives such as create_material, list_materials, or set_parameter. It does not mention prerequisites (e.g., the geometry node must exist, the material must already be created) or context for when this is the right choice.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.