pixelart_draw_polygon

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

Annotations indicate idempotentHint=true and readOnlyHint=false. The description adds behavioral context by explaining that the polygon can be an outline or filled based on the 'fill' parameter. It also mentions the return type ('Confirmation string'). No contradictions with annotations.

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 concise with five short sentences. The first sentence states the core action, the second provides usage guidance, the third lists parameters, and the last two note the return. No unnecessary words or padding.

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?

Given the tool's moderate complexity (4 parameters, one nested object) and low schema coverage, the description covers essential purpose and usage but lacks details like coordinate system, error conditions, or behavior for invalid input. It is adequate but not comprehensive.

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 for the top-level 'params' property is 0%, but sub-properties have descriptions for 'color' and 'points'. The description lists all parameters ('canvas_id, points (>=3 [x,y] pairs), color, fill') and adds minimal info (minimum points). However, it does not explain the 'fill' parameter beyond its presence, and relies on the schema for detailed constraints.

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 'Draw a polygon (outline or filled) from a list of vertex points.' It uses a specific verb ('Draw') and resource ('polygon'), and explicitly distinguishes itself from sibling tools draw_rect and draw_circle by providing use cases where they fall short.

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 explicitly states when to use this tool: 'for shapes that draw_rect/draw_circle can't express (roof slopes, tree silhouettes, diagonal terrain edges, etc).' This provides clear guidance on alternatives and context, making it easy for an agent to decide.

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