blender_create_material

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already signal that this is a mutating, non-idempotent operation, and the description neither contradicts them nor adds meaningful side-effect context. It does not explain what happens when a material with the same name exists, how 'overwrite' behaves, or whether assignment replaces existing material slots. The phrase 'optionally assign' is present but vague.

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 purpose is front-loaded in a single clear sentence, and the example is compact and immediately usable. There is no filler or repeated schema information. The example earns its place by demonstrating realistic values and parameter relationships.

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?

With 10 parameters, no output schema, and only sparse annotations, a two-sentence description plus example is insufficient. Missing behavioral details such as overwrite semantics, return value, and relationship to sibling material-assignment tools leave an agent under-informed for correct invocation.

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 only 20%, so the description carries extra responsibility. The example does add practical meaning for name, base_color, metallic, roughness, emission_color, and emission_strength by showing a coherent glowing-metal configuration. However, it leaves ior, overwrite, assign_to, and response_format unexplained beyond their schema names.

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 clearly states a specific verb and resource: 'Create a Principled BSDF material and optionally assign it to objects.' This is unambiguous and matches the tool name. However, it does not explicitly contrast with sibling tools like blender_assign_material or blender_set_material_node, so it stops short of full differentiation.

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 a concrete example but no guidance on when to use this tool versus alternatives. There are no mentions of exclusions, prerequisites, or why an agent should choose this over blender_assign_material or blender_generate_pbr_set. Usage context is only implied by the example.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.