Create Circle

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

The annotation readOnlyHint=false already signals a mutating operation, and the description adds that the operation creates a circle at a specific center and radius. It does not describe side effects beyond creation, but for a simple 'create' tool this is acceptable and not contradictory with annotations.

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 with no wasted words. It communicates the core operation and the essential parameters immediately while leaving parameter details to the fully covered schema.

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 low-complexity creation tool with a fully described schema and an output schema present, the description covers the essential invocation context. The main gaps are lack of usage guidance and no mention of optional parameter behavior, but the schema fills those gaps adequately.

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 description coverage is 100%, so the structured schema already documents all five parameters. The description adds minimal meaning beyond the schema, mainly linking cx/cy to center coordinates and radius to the given radius, but it does not enrich optional parameters like color or layer.

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 states a specific action and resource: 'Create a circle at (cx, cy) with given radius.' This clearly differentiates entity_create_circle from sibling creation tools like entity_create_arc, entity_create_ellipse, and entity_create_rectangle by entity type and defining parameters.

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 use when a circle entity needs to be created, but it does not explicitly state when to choose this over alternatives or mention any exclusions. For a straightforward creation tool this is minimally adequate, but there is no explicit routing guidance.

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