mat_create_multi_sub

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

Annotations already set readOnlyHint=false and destructiveHint=true, indicating a write operation with potential destructive effects. The description adds the behavioral detail that slots start empty and need to be filled later, but does not disclose any side effects like overwriting existing materials or behavior when assigning to objects. Since annotations carry the safety profile, the description provides modest additional context.

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 concise, with the main purpose stated first and the workflow in a second sentence. Providing bilingual text doubles the length, but each section is compact and to the point. No unnecessary filler; it gets the job done efficiently.

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 simple creation tool with no output schema, the description covers the essential purpose, the count parameter, the subsequent filling workflow, and the intended use with face material IDs. The optional 'objects' parameter is mentioned in the schema but not elaborated, yet that's covered by the parameter description. Overall, an agent can use this tool correctly with the given information.

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 schema already provides descriptions for all three parameters, achieving 100% coverage. The tool description reinforces the meaning of count (number of sub-slots) and mentions the workflow of filling slots, but doesn't add substantial new semantic information beyond the schema. Baseline 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 states a clear action ('Create a Multi/Sub-Object material') with a specific resource type and the key parameter (count). It distinguishes from sibling material creation tools by specifying the multi/sub-object nature and the workflow for filling sub-slots. The mention of face material IDs further clarifies its unique 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 explains the intended use: create material with count, then fill slots with mat_set_sub_material, and use in combination with face material IDs. This gives clear context for when the tool is appropriate. It doesn't explicitly rule out alternatives, but the workflow guidance is sufficient.

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