rhino_get_area

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

Annotations already declare the tool as readOnly, idempotent, and non-destructive, so the description need not repeat those. The description adds the object types it works on, which is useful context. However, it does not mention that the operation is non-mutating beyond what annotations provide, nor does it describe any edge cases or units. With annotations covering the safety profile, a 3 is appropriate.

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 a single concise sentence that clearly states the action and the object types. It is front-loaded and contains no unnecessary words, earning a perfect score for conciseness.

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?

While an output schema exists (so return values need not be described), the description lacks essential usage context. It does not explain that the guid parameter refers to an existing Rhino object previously obtained via get_objects or similar, nor does it clarify the selection of among surface, brep, or mesh. For a tool with a single parameter and no schema-level documentation, this is a significant gap.

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 0%, meaning no parameter documentation exists in the schema. The description does not add any information about the 'guid' parameter, such as how to obtain it or what objects are valid. The agent is left without guidance on what to pass, making the parameter semantics very weak.

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 the verb 'Calculate' and the resource 'surface area', and specifies the object types (surface, brep, mesh). This distinguishes it from sibling tools like rhino_get_volume and rhino_get_length, which are for different measurements. The purpose is unambiguous.

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 usage for area calculations on specific geometry types, but it does not explicitly state when to use this tool versus alternatives or mention any prerequisites. It does not reference rhino_get_volume or rhino_get_length as alternatives, leaving some inference to the agent. However, the scope is clear enough for a basic call.

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