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Create Polygon

create_polygon

Draw a regular polygon in the most recent sketch by specifying the number of sides and circumradius. Optionally set the center coordinates.

Instructions

Draw a regular polygon in the most recent sketch

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "sides": "<sides>",
      "radius": "<radius>"
    },
    "name": "create_polygon"
  }
}

Input Schema

Name	Required	Description
`sides`	Yes
`radius`	Yes	Circumradius (cm)
`center_x`	No
`center_y`	No
`center_z`	No

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Sep 11, 2026

TDQS

B3/5.0

Behavior3/5

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

Annotations indicate this is a non-readOnly, non-idempotent, non-destructive operation, which the description aligns with by implying creation ('Draw'). However, the description adds minimal behavioral context beyond annotations—it doesn't specify if it modifies existing geometry, requires specific sketch states, or has side effects like auto-constraints.

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

Conciseness5/5

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

The description is a single, efficient sentence with no wasted words. It front-loads the core action ('Draw a regular polygon') and adds necessary context ('in the most recent sketch'), making it easy to parse quickly.

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

Completeness2/5

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

Given the tool's complexity (5 parameters, creation operation), lack of output schema, and low schema coverage, the description is incomplete. It doesn't cover parameter meanings, behavioral nuances, or usage context, leaving gaps for an AI agent to infer correctly.

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

Parameters2/5

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

Schema description coverage is low (20%), with only 'radius' having a description ('Circumradius (cm)'). The description adds no parameter semantics, failing to explain 'sides' (number of polygon edges), 'center_x/y/z' (3D coordinates), or how they interact. For 5 parameters with poor schema coverage, this is inadequate.

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 action ('Draw') and resource ('a regular polygon'), specifying it occurs 'in the most recent sketch'. It distinguishes from siblings like 'draw_circle' or 'draw_rectangle' by focusing on polygons, but doesn't explicitly differentiate from other polygon-related tools (none in the list).

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

Usage Guidelines2/5

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

No guidance on when to use this tool versus alternatives is provided. The description mentions 'most recent sketch', implying a sketch must exist, but doesn't state prerequisites or compare to other drawing tools like 'draw_circle' or 'draw_rectangle' for shape selection.

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

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