Fill an elliptical region on the design layer using coordinates, dimensions, and color to add rounded shapes to pixel art.
Fill an ellipse bounded by (x,y,width,height) on the design layer.
| Name | Required | Description | Default |
|---|---|---|---|
| x | Yes | ||
| y | Yes | ||
| name | Yes | ||
| slot | Yes | ||
| color | Yes | ||
| scale | No | ||
| width | Yes | ||
| height | Yes | ||
| plan_id | No | ||
| output_dir | No |
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the behavioral burden, and it does communicate the core effect: a filled ellipse is drawn in the design layer. However, it does not disclose whether existing pixels are overwritten, how color/scale are applied, or what other side effects occur.
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?
A single front-loaded sentence with no filler. Every word contributes the core shape, geometry, and target layer.
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?
Despite having an output schema, the tool has 10 parameters, 7 required, and no schema descriptions or annotations. The description only covers geometry and location, leaving most parameters, preconditions, and side effects undocumented.
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%, and the description only clarifies x, y, width, and height via 'bounded by'. Required parameters name, slot, and color, plus optional scale, plan_id, and output_dir, are left unexplained.
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 uses a specific verb ('Fill') and resource ('an ellipse bounded by (x,y,width,height)') and names the target ('design layer'). This clearly differentiates it from sibling tools like fill_rect, stroke_rect, and draw_line.
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?
It implies the tool is for drawing a filled ellipse onto the design layer, but it does not explicitly state when not to use it or mention alternatives such as fill_rect for rectangles. Usage is inferred rather than directly guided.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.