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

Annotations already declare readOnlyHint=false, destructiveHint=false, idempotentHint=false and openWorldHint=false. The description adds genuinely useful context beyond that: the output artifact format (GLB) and the credit cost of each mode, which is exactly the kind of resource-impact information an agent needs before invoking a paid generation.

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?

Two short sentences with zero filler: the first states the action and artifact, the second states the cost tradeoff. The most decision-relevant information is front-loaded.

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?

There is no output schema, and the description does not say what the call returns (asset id, URL, or async job) or how to retrieve the finished model, despite check_generation being a sibling. For a paid, likely asynchronous generation tool with six parameters, that is a meaningful omission.

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 83% and three parameters have enums with documented meanings (mode, type, style, bodyType), so the schema does most of the work. The description echoes the mode cost distinction but adds no meaning for seed or other parameters, so the baseline 3 applies.

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 a specific verb ('Generate'), resource ('a 3D model'), output format ('GLB') and input ('from a prompt'), which clearly separates it from siblings like animate_3d_model, rig_3d_model, or render_3d_sprites. It does not explicitly name a sibling it is not, so it falls just short of 5.

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 credit costs (45 for game-ready, 15 for lq draft) imply a quality/cost tradeoff that hints at when to use each mode, but there is no explicit when-to-use or when-not-to-use guidance and no mention of alternatives such as regenerate vs. edit.

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