Skip to main content
Glama
mystify59

self-host-fusion360-mcp

by mystify59

fusion_sketch_polygon

Create a regular polygon in a Fusion 360 sketch by defining center, circumradius, and side count (>=3). Supports plane, rotation, and sketch selection for precise placement.

Instructions

Draw a regular polygon (mm) by center, circumradius, and side count (>=3).

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
xNo
yNo
planeNoxy
sidesYes
radiusYes
sketchNo
rotation_degNo

Schema Changelog

Changes observed during successful MCP inspections.

  1. First observedv0.6.0

TDQS

B3.4/5.0
Behavior3/5

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

Annotations indicate readOnlyHint=false (mutation), destructiveHint=false (non-destructive), but the description does not elaborate on behavioral aspects beyond drawing. It doesn't mention whether the polygon is added to a sketch, whether it requires an existing sketch or creates one, or any side effects on existing geometry. The description is somewhat redundant with the title and doesn't disclose additional behavioral details that an agent might need.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, concise sentence that front-loads the essential details (draw polygon, unit, construction method). It's efficient and direct, with no filler. However, it could be slightly more structured to include parameter hints, but its brevity is a strength.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool complexity (7 params, no output schema, no annotation coverage), the description is minimally adequate. It covers the core purpose but misses important contextual details like how the polygon interacts with existing sketches, what the 'plane' parameter does, and what the return value is. The description leaves gaps that an agent would need to infer or test.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0% and there are 7 parameters, so the description must compensate. It explains the meaning of 'radius' (circumradius) and 'sides' (count >=3), which is helpful, but it doesn't explain parameters like x, y, plane, rotation_deg, or sketch. The description adds some meaning but leaves many parameters unexplained, relying on their titles which are not self-explanatory for all.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool draws a regular polygon with key parameters (center, circumradius, side count) and includes the unit (mm) and constraint (sides >=3). It distinguishes from similar sketch tools (e.g., fusion_sketch_rectangle, fusion_sketch_circle) by specifying 'polygon' and its specific parameters, though it doesn't explicitly name a sibling.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description implies this tool is for creating a polygon in a sketch, but it doesn't explicitly state when to use it versus other sketch tools (like line or arc) or when not to use it. It doesn't mention prerequisites such as needing an active sketch or document. There's no alternative mentioned.

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

Deploy Server

Other Tools