rhino_subd_expand_edges

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

Annotations are absent, so the description carries the full behavioral burden. It discloses the core geometric intent, but does not say whether the operation mutates the existing SubD, creates new geometry, what happens with no valid edge selection, or what side effects occur. For a mutating tool this is a meaningful transparency 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 main sentence is concise and front-loaded with the action and target. However, the Args section adds little beyond restating distance and introduces the controller argument not present in the schema, which is a structural inconsistency in an otherwise short definition.

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 mutating SubD tool with no annotations, the description is under-specified: it does not clarify in-place modification versus new object creation, distance units, selection requirements beyond 'selected,' or failure behavior. The output schema exists, so return details are less critical, but key execution context is still missing.

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 has no description coverage, and the description only restates the distance parameter as 'Expansion distance.' It does not specify units, valid range, or whether negative values are meaningful. It also lists a 'controller' argument in prose that is absent from the input schema, creating ambiguity about the actual call signature.

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 ('Expand') applied to a specific resource ('selected SubD edges') with a measurable condition ('by a given distance'). This is clearly distinguishable from sibling SubD tools like rhino_subdivide or rhino_offset_subd, which do different operations.

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 implies the tool is used when SubD edges are selected and need to be expanded outward, but it gives no explicit when-not guidance or alternatives. It does not mention how this relates to similar tools such as rhino_offset_subd, rhino_subdivide, or other edge-editing operations.

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