create_ellipse

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

With no annotations, the description carries the full burden of behavioral disclosure. It only states that it creates a node on the canvas, which is the core action, but does not mention side effects (e.g., selection changes, undo behavior), prerequisites, permissions, or what happens if required parameters are missing. This is minimal for a mutation tool without annotation support.

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 that states the purpose immediately and appends a concise list of use cases. Every word contributes, with no fluff or 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?

Given the schema fully documents parameters and there is no output schema, the description adequately explains the tool's purpose. However, it lacks any mention of return values, error behavior, or what happens after creation (e.g., node selection), which would make it more complete for an agent to safely invoke.

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 100% description coverage for all 8 parameters, so the baseline is 3. The description adds a subtle hint about circular shape (width=height) and typical uses, but does not materially enhance understanding of the parameters beyond the schema, so it stays at baseline.

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 ('Create'), the resource ('ellipse or circular shape node'), and the location ('on the canvas'), and differentiates it from siblings like create_rectangle by emphasizing the circular/elliptical shape and typical use cases (avatars, status badges, circular buttons, indicator dots).

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 provides explicit use cases ('ideal for user avatars, status badges, circular buttons, and indicator dots'), which tells the agent when to select this tool over alternatives. However, it does not explicitly name alternatives or state when not to use it, so it falls short of full routing guidance.

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