fusion_sketch_arc

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

Annotations already indicate readOnlyHint=false (mutation) and openWorldHint=true, so the description's 'Draw' is consistent but adds little new. It mentions 'mm' for units, which is a minor extra, but does not disclose side effects, behavior when sketch is null, or error conditions. Given the annotations cover the mutating nature, the description adds only marginal value beyond them.

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 concise sentence with no fluff. It front-loads the action and essential point definitions, then adds a practical use case. Every word earns its place, and it is appropriately sized for the tool's simplicity.

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 description covers the main coordinate parameters and a use case, but lacks details on how the optional 'plane' and 'sketch' parameters behave, what happens if no sketch is provided, and any return value or side effects. For a tool with 8 parameters and no output schema, this leaves some ambiguity, though the core function is understandable.

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?

With 0% schema description coverage, the description must compensate. It explains the six required coordinates as start, through, and end points, which is essential meaning. However, it does not explain the optional 'plane' and 'sketch' parameters, leaving their roles implicit. The core parameters are well defined, but coverage is incomplete for all 8 parameters.

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 draws a 3-point arc with specific point roles (start, through, end), and names the unit (mm). It distinguishes itself from sibling sketch tools like line, circle, and spline by its explicit 3-point arc definition, making its 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?

The description gives a specific use case ('useful as a sweep/revolve path') but does not explicitly compare to alternatives or state when not to use it. It implies this tool is for arcs defined by three points, but it lacks guidance on choosing it over other sketch tools like spline or circle, or when a different construction method is preferable.

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