add_circle

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

With no annotations provided, the description carries the full transparency burden. It discloses that the circle is 'fully-constrained' and that coordinates are in 'sketch-local space,' which is useful. However, it does not mention permissions, error conditions, or side effects, and the mutation aspect is only implicit in the verb 'Add.'

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 sentence followed by a compact argument list. It is front-loaded with the primary purpose and contains no redundant words. The structure is clear, scannable, and appropriately sized for a simple tool.

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 tool with 5 parameters, no annotations, and no visible output schema, the description covers the essential context: what it does, the parameters, and the coordinate space. It does not explain return values, but the presence of an output schema may cover that. It is sufficiently complete for a basic geometry-adding operation.

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?

The schema provides no descriptions for its 5 properties (0% coverage), so the parameter list in the description is essential. It gives brief definitions for each parameter and adds context like 'sketch-local space' for x and y. This compensates for the schema gap, though it could detail units or coordinate system further.

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 action: 'Add a fully-constrained circle to a sketch, centered at (x, y).' This is a specific verb+resource that distinguishes it from sibling tools like add_rectangle and add_polygon. The 'fully-constrained' detail adds precision about the geometry's behavior.

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 when to use this tool (when adding a circle to a sketch) but does not explicitly address when to use it instead of alternatives like add_rectangle or add_polygon. No exclusions or alternative tools are mentioned, leaving usage guidance at an implied level.

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