cad_sketch_circle

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

With no annotations, the description must fully disclose behavior. It states the tool adds a circle and returns entityId, but does not explain side effects (e.g., whether the circle is added to an active sketch, if any sketch must be started first) or constraints (e.g., coordinate system, units). The behavioral contract is incomplete.

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 extremely concise with two sentences. It front-loads the primary action and return value. However, the conciseness sacrifices completeness, but as a single dimension it is well-structured.

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 4 parameters and no output schema or annotations, the description lacks essential context. It does not explain the required sessionId parameter, nor does it specify coordinate systems, units, or the requirement of an active sketch. The description is too sparse to fully inform invocation.

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 0%, so the description must clarify parameters. It adds meaning to 'construction' (reference circle), but sessionId is unexplained, center and radius are only implied by their type. The description does not fully compensate for the missing schema descriptions.

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 tool adds a circle, which is a specific verb and resource. It differentiates from sibling tools like cad_sketch_line or cad_sketch_arc. It also mentions the return value (entityId), making the purpose unambiguous.

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?

No guidance is provided on when to use this tool versus alternatives (e.g., when to use a circle vs. an arc or other sketch primitives). There is no mention of prerequisites or context, so usage decisions are left entirely to the agent.

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