rhino_radius

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

The description notes that the tool is 'interactive' and operates on a 'selected' arc or circle, which conveys that a selection is required and that the user may need to interact with Rhino. Since no annotations are present, the description carries the full burden, and it does not explicitly state whether the tool modifies the document or what happens if no valid arc/circle is selected.

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 short and front-loaded, with the core purpose in the first line. The Args/Returns boilerplate is mostly unnecessary but does not add significant noise.

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 zero-parameter measurement tool with an output schema, the description covers the essential operational context: what is measured, the object types involved, and that the interaction is interactive. It could add more detail about selection behavior or result contents, but the core invocation requirements are understandable.

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 has zero parameters, so there is little to document. However, the description's docstring references a 'controller: RhinoController instance' argument that is not reflected in the schema, which is a minor mismatch and could confuse an agent about what arguments are expected.

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 a specific action ('Measure') and resource ('radius of a selected arc or circle'), which makes the tool's purpose immediately understandable. It does not explicitly contrast itself with sibling measurement tools, but the radius-specific resource is distinct enough that confusion is unlikely.

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 tool's use case is implied: use it when you need the radius of an arc or circle. However, it provides no explicit guidance on when to prefer this tool over alternatives like rhino_curve_length or rhino_distance, nor does it mention exclusions.

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