rib

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

Annotations already declare this is a non-readonly, non-destructive, non-idempotent mutation. The description adds useful behavioral detail about thickness centering, material growth direction, and flip behavior when the rib does not reach the part.

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 front-loaded with the core definition and then moves efficiently through the non-obvious parameter semantics. It is appropriately sized for a CAD feature tool and every sentence adds information.

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?

Given the presence of an output schema and annotations, the description covers the key geometric behavior and most parameters. It could be stronger by briefly clarifying draft_angle_deg or the active-sketch prerequisite, but it is largely complete for correct invocation.

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 only 40%, so the description must compensate. It explains thickness_mm, one_side, direction, and flip_material well; draft_angle_deg is left to the schema, which does provide a basic description and bounds.

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 CAD feature, 'Rib from the last sketch', and explains the geometric basis of a rib. It is clear enough to distinguish from siblings like extrude or fillet, but it does not explicitly name alternatives or contrast its role with them.

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 usage context by saying the rib usually comes from an open line between walls drawn on a mid-plane sketch. It does not explicitly say when to use this tool instead of extrude, sweep, or other feature tools, nor does it state prerequisites beyond 'last sketch'.

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