Crop an Aseprite canvas to a specific x, y, width, and height rectangle. Use it to trim or enlarge the canvas for pixel art and animation edits.
Crop the canvas to the rectangle (x, y, width, height).
The resulting canvas is subject to the same dimension/area caps as `create_sprite`
(a "crop" to a larger rectangle grows the canvas).
| Name | Required | Description | Default |
|---|---|---|---|
| x | Yes | ||
| y | Yes | ||
| width | Yes | ||
| height | Yes | ||
| filename | Yes |
Changes observed during successful MCP inspections.
v0.10.0Input schema / properties / filename / titleRemoved value: -"Filename"Input schema / properties / height / titleRemoved value: -"Height"Input schema / properties / width / titleRemoved value: -"Width"Input schema / properties / x / titleRemoved value: -"X"Input schema / properties / y / titleRemoved value: -"Y"Input schema / titleRemoved value: -"crop_spriteArguments"v0.7.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare destructiveHint=true and readOnlyHint=false, so the safety profile is covered. The description adds genuinely useful behavior beyond that: the resulting canvas inherits create_sprite's dimension/area caps, and a crop to a larger rectangle GROWS the canvas rather than failing — a counterintuitive trait worth surfacing.
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?
Two tight sentences with the core action front-loaded and the surprising edge-case behavior immediately after. No filler.
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 destructive 5-parameter mutation with no output schema and zero schema description coverage, the description covers crop semantics well but omits the filename parameter, origin convention, and out-of-bounds/clamping behavior. Annotations cover the safety profile, so the remaining gap is moderate.
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 none of the five parameters are documented in the schema. The description names x, y, width, height but never says x/y are the top-left corner or how out-of-bounds values behave, and the required `filename` parameter is not mentioned at all.
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?
States a specific verb (crop) and resource (canvas) and identifies the exact parameters that define the rectangle. It doesn't explicitly differentiate itself from adjacent transforms like trim_sprite, resize_canvas, or scale_sprite, though the parenthetical clarifies its unusual grow-on-larger-rectangle semantics.
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 when-to-use guidance is given and no alternatives are named, despite siblings like trim_sprite and resize_canvas that overlap conceptually. The note about area caps implies constraints but does not tell the agent when to prefer this tool.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.