catia_variable_fillet

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

Annotations already indicate a non-read-only, non-idempotent, non-destructive operation. The description adds the core behavior of creating a rounded edge with a variable radius, but it does not explain edge start/end direction, prerequisites, or failure behavior, so it adds only moderate context beyond the annotations.

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, front-loaded sentence with no filler. It is concise and readable, but slightly too terse to carry important operational context such as edge direction or selection, leaving those details entirely to the schema.

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 CAD feature-creation tool with no output schema, the description covers the main operation but leaves gaps around how start and end are determined, how to obtain the edge token, and what propagation means in practice. The well-described schema compensates partially, but contextual guidance remains average.

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 100%, and each parameter already has a clear description, including the edge reference token, radii in mm, and tangency propagation. The tool description only restates the start/end radius concept and adds no meaning beyond the schema, so the baseline 3 is appropriate.

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 verb ('Round') and resource ('an edge'), and distinguishes this from sibling fillet tools by specifying that the radius varies along the edge between a start and end radius. This is unambiguous and immediately identifies the intended operation.

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 this tool is for variable-radius filleting, but it does not explicitly contrast it with constant-radius catia_fillet or other fillet variants, nor does it state when not to use it. The usage context is inferable but not directly articulated.

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