create_circle

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

With no annotations, the description fully discloses behavior: requires active sketch, geometry is non-parametric (cannot resize post-hoc), returns center/radius/diameter, and suggests rebuilding from fresh part for resize. This goes beyond basic operation.

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 well-structured with a clear header, parameter list, return, common uses, example, caveats, and related tools. It is front-loaded and every section adds value without redundancy.

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?

Despite having no output schema, the description covers return values. It includes prerequisites, limitations, and alternative tools. For a simple drawing tool, it is comprehensively complete.

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 coverage is 0%, so the description compensates by explaining all 5 parameters: cx_mm, cy_mm, radius_mm, and aliases center_x_mm, center_y_mm. It clarifies the constraint to pass one name per axis and that radius must be positive, with an example.

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 'Draw a circle on the active sketch' with a specific verb and resource. It distinguishes itself from siblings by mentioning add_bolt_circle as an alternative for bolt patterns, and provides common autoparts uses.

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 explains the prerequisite (requires active sketch) and explicitly names an alternative tool (add_bolt_circle). It implies when to use via common uses, but does not explicitly state when not to use (e.g., for parametric circles).

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