mat_create_generic

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

Annotations already declare destructiveHint=true and readOnlyHint=false, covering the mutating nature. The description adds the validation step with mcpEnsureClass, which is useful but does not disclose return values or error behaviors. Given the annotations, this is adequate but not rich.

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 extremely concise: two sentences in English (plus Chinese) that front-load the purpose and include a usage hint. Every sentence earns its place, with no redundancy or filler.

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 in a domain with many dedicated alternatives, the description provides the critical routing information (use for obscure materials) and a discovery path (get_class_properties). It does not explain error handling or return format, but the validation mention and schema coverage make it sufficiently complete for an agent to call correctly.

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?

The input schema covers all three parameters with descriptions and examples, achieving 100% coverage. The description adds no extra parameter semantics beyond what the schema already provides, so the baseline score of 3 is appropriate.

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 the tool's function: creating a material from any class name, explicitly validated with mcpEnsureClass. It differentiates from dedicated material creation tools by specifying it is for obscure materials lacking a dedicated tool, which distinguishes it from mat_create_standard and similar siblings.

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 gives explicit guidance on when to use this tool (obscure materials without a dedicated tool) and how to discover class names via get_class_properties. It implies that if a dedicated tool exists, it should be used instead, though it does not explicitly name alternatives. This is clear context but lacks explicit exclusions.

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