Skip to main content
Glama

draw_shape

Draws pixel-art geometric shapes (line, rectangle, circle) on a canvas using specified coordinates, color, and optional fill.

Instructions

Draws a pixel-art rasterized geometric primitive (line, rect, circle).

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
x1YesStarting X / Center X / Rect X
x2NoEnding X / Rect Width / Circle Radius
y1YesStarting Y / Center Y / Rect Y
y2NoEnding Y / Rect Height
colorYesHex color or palette index
shapeYesShape type to draw
filledNoWhether the shape is filled (default: false)
canvas_idYesTarget canvas ID
Behavior2/5

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

No annotations are provided, so the description must disclose behavioral traits. It only says 'Draws...', which indicates mutation but does not mention whether it overwrites existing pixels, handles coordinate bounds, or returns any confirmation. The effect on the canvas and any side effects are left undefined.

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?

A single sentence that immediately names the action and scope, with no fluff. The core purpose (drawing a primitive) is front-loaded, and the list of shapes is concise and informative.

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?

The tool has 8 parameters with shape-dependent semantics (x1/x2 roles change per shape) and an optional filled flag, but the description provides no guidance on these complexities. It also lacks information about coordinate systems, clipping, or interaction with existing pixels. With no output schema, the agent is left with incomplete context for correct invocation.

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 100%, so the input schema documents each parameter. The description adds no additional meaning beyond what the schema already provides (e.g., the ambiguous meaning of x1/x2 based on shape). Given high coverage, the baseline of 3 is appropriate; the description does not compensate for schema ambiguities.

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

Purpose5/5

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

The description states a specific verb ('Draws'), a resource ('pixel-art rasterized geometric primitive'), and enumerates the exact shapes supported ('line, rect, circle'). This makes the tool's purpose immediately identifiable and clearly distinguishes it from sibling tools like set_pixel or flood_fill.

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 the tool is for drawing geometric shapes but provides no explicit guidance on when to choose it over siblings (e.g., draw_shape vs set_pixel_batch for multiple pixels). There are no stated exclusions or if-then conditions, leaving the agent to infer usage from the shape list.

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

Install Server

Other Tools

Latest Blog Posts

MCP directory API

We provide all the information about MCP servers via our MCP API.

curl -X GET 'https://glama.ai/api/mcp/v1/servers/al3duc/text2d-mcp'

If you have feedback or need assistance with the MCP directory API, please join our Discord server