draw_rectangleCreates a rectangle in the most recent Fusion 360 sketch using width and height, with optional origin coordinates in cm unless specified.
Draw a rectangle in the most recent sketch. Unless a parameter says otherwise, lengths and coordinates are in cm (not mm) and angles in degrees.
| Name | Required | Description | Default |
|---|---|---|---|
| width | Yes | ||
| height | Yes | ||
| origin_x | No | ||
| origin_y | No | ||
| origin_z | No |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=false, idempotentHint=false, destructiveHint=false, so the mutation profile is covered. The description adds genuinely non-obvious unit conventions (cm not mm, degrees) but says nothing about failure when no sketch exists, what the call operates on, or whether the rectangle is added as a constrained entity.
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?
Two tight sentences with zero filler, purpose front-loaded and the unit caveat placed second where it belongs. Every clause earns its place.
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?
With no output schema and no meaningful annotations, the description must carry more weight than it does. It omits prerequisites, failure modes, and return behavior for a 5-parameter mutation tool, leaving real gaps an agent would hit at call time.
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% across 5 parameters, so the description must compensate and largely does not. It gives unit conventions but never explains what origin_x/y/z represent (corner vs. center) or clarifies width vs. height semantics, leaving the parameters effectively undocumented.
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?
States a specific verb (draw) and resource (rectangle) plus the target context (the most recent sketch), which no sibling tool claims. It does not explicitly distinguish itself from draw_line/draw_circle, but the scope 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 phrase 'in the most recent sketch' implies the tool requires an existing sketch, which is useful context, but it never states this as a prerequisite or says when to prefer a rectangle over draw_line/create_box. Usage is inferable but not spelled out.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.