rhino_subd_sphere

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states that the tool creates a SubD sphere, but does not disclose whether it adds to the current document, replaces any existing object, affects selection state, or requires any particular layer/units context. For a mutation tool, this is a significant gap.

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 and front-loaded with the core action, followed by a terse Args list. It avoids unnecessary prose, but the inclusion of a non-existent 'controller' parameter is a minor structural flaw that prevents a perfect score.

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?

The tool is simple and the description covers the basic creation action and parameter meanings, but it omits usage context such as whether the sphere is added to the active document, how subdivisions affect the result, and the role of the output schema. The schema provides defaults but the description alone is not fully self-sufficient, especially regarding the controller mismatch.

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 description provides definitions for all five schema properties (x, y, z, radius, subdivisions), adding meaning beyond the bare property titles in the schema. However, it also lists a 'controller' parameter that does not exist in the input schema, which is a mismatch. This partial compensation and inconsistency justify a middle score.

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 specific verb and resource: "Create a SubD sphere primitive." This clearly distinguishes it from sibling tools like rhino_subd_box or rhino_cmd_sphere (likely NURBS), and the SubD prefix makes its domain explicit. It is not a tautology; it adds the primitive context.

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?

There is no guidance on when to use this tool versus alternatives. It does not mention that this creates a SubD sphere specifically, or contrast it with rhino_cmd_sphere for NURBS spheres, nor does it state any preconditions like needing an active document. The usage context is only implied by the name and description.

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