draw_circle

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

Annotations already declare it a non-readonly, non-destructive, non-idempotent write, so the safety profile is partially covered. The description adds nothing beyond that: no statement about required drawing state, whether the circle is drawn on the current layer by default, or what happens on invalid radius/center.

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?

It is a single front-loaded clause with zero padding, so it is structurally clean. The brevity is under-specification rather than genuine efficiency, which caps it below a 4.

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 geometry-creation tool this is too thin: no coordinate system or unit context, no dependency on an open drawing, and no routing among the many draw_* siblings. The output schema does excuse it from explaining return values, but the input-side context is missing.

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 80% and the schema itself documents color, layer, center, and linetype well, so the baseline of 3 applies. The description contributes no additional parameter meaning, but it also isn't needed to compensate for large gaps.

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?

"Draw a circle" names a verb and resource, but it is a verbatim restatement of the tool name draw_circle and adds no distinguishing scope. It gives no way to tell it apart from siblings like draw_arc, draw_ellipse, or draw_polygon.

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?

There is no when-to-use guidance, no preconditions (e.g. an open drawing being required), and no mention of alternatives such as draw_arc or draw_batch. The agent is left to infer everything from the name.

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