add_fillet

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

No annotations are provided, so the description carries the full burden. It usefully discloses failure behavior ("A refusal names the edges the radius does not fit") and return information ("Returns the number of edges filleted and the mass properties"), though it does not discuss prerequisites or feature-creation side effects.

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 long and dense, but it is front-loaded with the core purpose and every subsequent sentence adds operational detail about edge selection, variable radii, and propagation. It is appropriately sized for a complex CAD operation, though slightly verbose.

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 no annotations, no output schema, and 0% schema description coverage, the description supplies substantial behavioral and parameter context, including return values and failure handling. It remains incomplete only because the name parameter is never described.

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%, so the description must compensate. It gives rich meaning for edges, radii_at_mm, skip_shorter_mm, and tangent_propagation, but does not explain the name parameter, leaving one of six parameters undocumented.

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 verb and resource: "Round edges of the current part with one constant radius (mm)." The operation is clear, but the description does not explicitly differentiate it from sibling tools such as add_chamfer or add_full_round.

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?

Usage is implied by the opening sentence and extensive edge-selection guidance, but there is no explicit when-to-use guidance, no when-not-to-use conditions, and no named alternatives among the sibling tools.

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