create_ellipse

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

Annotations already declare readOnlyHint=false and destructiveHint=true, so the description does not need to restate mutation. It adds minimal context by implying a creation operation, but it does not disclose any side effects, undo behavior, or requirements. With annotations covering the destructive nature, a 3 is appropriate.

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 very short and to the point, with bilingual content. It is front-loaded with the core purpose. However, it is so minimal that it may under-specify rather than being efficiently concise. It earns a 4 for being compact and clear.

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 17 parameters, the description is incomplete. It does not indicate which parameters are applicable, does not describe return values, and does not mention any prerequisites. Even with annotations, the description is insufficient for an agent to call this tool correctly without exploring the schema deeply and guessing at relevance.

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 100%, but the description only explains length and width. Many parameters in the schema (sides, turns, radius, etc.) are irrelevant to an ellipse and are not filtered out. The description fails to clarify which parameters actually apply to ellipse creation, leaving the agent confused about which of the 17 parameters to use. It adds little value beyond the schema.

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 it creates an ellipse spline and specifies that length/width control the major/minor axes. It is a specific verb+resource, but it does not differentiate from sibling tools like create_circle or create_ngon beyond the shape type. The purpose is clear but not heavily detailed.

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 guidance on when to use this tool versus alternatives. It does not mention when an ellipse is preferred over other spline primitives, nor any prerequisites or context. The agent is left to infer usage from the name alone.

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