ase_select_ellipseSelect an elliptical region in a pixel-art canvas by providing its bounding box coordinates and dimensions. Use this to set the active selection for subsequent editing operations.
Set the server-side selection to an ellipse (bounding box).
| Name | Required | Description | Default |
|---|---|---|---|
| x | Yes | ||
| y | Yes | ||
| width | Yes | ||
| height | Yes |
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description must carry the full behavioral burden. It states that the selection is set to an ellipse but does not disclose whether this replaces the existing selection, how coordinates are interpreted, whether bounds are clamped, or what side effects occur on other selection-dependent tools.
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 a single sentence with no filler and gives the core concept efficiently. It is appropriately front-loaded, though it errs on the side of under-specification.
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?
For a simple four-parameter tool with an output schema, the description is minimal but not sufficient. It lacks coordinate semantics, interaction with the existing selection, and any guidance about how this relates to other selection tools, leaving an agent to guess important call-time details.
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 coverage is 0%, so the description must compensate for the four undocumented integer parameters. The phrase 'ellipse (bounding box)' implies x, y, width, and height describe a bounding rectangle, but it does not explain the origin, units, or whether width/height are diameters or radii.
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 identifies the operation as setting the selection to an ellipse-shaped region, with 'server-side' adding relevant context. It distinguishes itself from sibling tools like ase_select_rectangle and ase_draw_circle, though it does not explicitly contrast with them.
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?
No guidance is given about when to use this tool instead of alternatives such as ase_select_rectangle, ase_select_all, or ase_deselect. The agent must infer usage solely from the tool name and the word 'ellipse'.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.