Create a new Principled BSDF material with adjustable base color, metallic, and roughness for Blender scenes.
Create a new Principled BSDF material. base_color is [R, G, B, A] (0-1 range).
| Name | Required | Description | Default |
|---|---|---|---|
| name | No | Material | |
| metallic | No | ||
| roughness | No | ||
| base_color | No |
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v0.1.0+hardened.2Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the full behavioral burden, but it only reveals the base_color input format. It does not disclose what happens on creation (e.g., whether the material is auto-assigned, how name conflicts are handled, or the effect of a null base_color).
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?
One sentence with the action front-loaded and zero filler. The base_color format note earns its place, though the brevity comes at the cost of omitted parameter semantics.
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 creation tool with 4 parameters, zero annotations, and 0% schema description coverage, this description is incomplete: three parameters are undocumented and creation side effects are not stated. The output schema covers return values, but that does not compensate for the missing input and behavioral 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 document the parameters, yet it only explains base_color's [R,G,B,A] format and 0-1 range. name, metallic, and roughness rely entirely on their names and defaults, leaving their semantics and valid ranges undocumented.
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?
States the verb (Create), resource (material), and specific type (Principled BSDF) in one clear clause. This distinguishes it from siblings like duplicate_material (copy existing) and create_shader_node (node-graph elements), so an agent can select it correctly without opening the schema.
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?
No guidance on when to create a new material versus reusing, duplicating, or modifying an existing one. The sibling set includes duplicate_material, assign_material, and set_material_property, but the description offers no selection criteria among them.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.