create_sketch_circle

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

With no annotations, the description carries full responsibility for behavioral disclosure. It only restates the faceId-wins precedence and the list_entities source, both of which already appear in the input schema. It does not mention whether the tool creates a new sketch or adds to an existing one, what it returns, or other side effects such as variable constraints beyond the schema descriptions.

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 three short sentences with the core purpose front-loaded, followed by surface-selection guidance and the precedence rule. There is no filler or unnecessary prose; the structure makes the most important information immediately visible.

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?

The rich schema covers all 12 parameters, defaults, units, and legacy fields, so invocation details are well supported. However, with no output schema and no annotations, the description omits tool-selection context versus other sketch creators, the return value, and whether the circle is created in a new sketch or an existing one. These are moderate gaps, but the schema prevents the definition from being inadequate.

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% and the parameter descriptions are detailed, covering defaults, units, legacy alternatives, and variable-driven behavior. The description adds no new parameter meaning—it rephrases the plane/faceId relationship already documented in the schema. Therefore the baseline of 3 is appropriate.

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 first sentence, 'Create a circular sketch,' clearly states the verb (create) and resource (circular sketch), and the word 'circular' differentiates it from sibling rectangle, line, and arc sketch tools. The surface-selection instruction reinforces what the tool operates on. The core function is 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?

The description gives no explicit comparison to siblings such as create_sketch_rectangle, create_sketch_line, or generic create_sketch, so tool selection is left mostly to inference from the name. It does provide within-tool guidance on choosing plane vs faceId, which is useful but is not the same as saying when to use this tool instead of alternatives. Usage context is implied, not explicit.

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