Define a rectangular area using x, y, width, and height to crop a sprite canvas, removing excess pixels outside the selected bounds.
Crop the sprite canvas to a rectangle.
| Name | Required | Description | Default |
|---|---|---|---|
| x | Yes | ||
| y | Yes | ||
| width | Yes | ||
| height | Yes | ||
| filename | Yes |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden of behavioral disclosure. 'Crop' implies a mutating operation, but the description does not state that it irreversibly modifies the sprite, how out-of-bounds coordinates are handled, whether the change is applied in place, or what the resulting canvas dimensions will be. This is a significant gap for a destructive operation.
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 terse sentence with no filler and a front-loaded verb. It is structurally clean, though its brevity contributes to the lack of operational detail.
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 five-parameter mutating tool with no annotations, no output schema, and zero schema descriptions, the description is not complete enough. An agent needs to know the coordinate system, the crop behavior relative to the existing canvas, whether the operation is destructive, and how filename maps to a sprite. None of this is addressed.
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 offers no parameter-level meaning. The names x, y, width, and height are self-evident individually, but the description does not clarify coordinate origin, units, whether width and height are relative to x/y, or how filename selects the target sprite. The description fails to compensate for the schema's complete lack of parameter documentation.
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 action ('Crop') and the resource ('sprite canvas') with a specific outcome ('to a rectangle'). It does not explicitly distinguish itself from the sibling resize_canvas, but the term 'crop' conveys a distinct operation well enough.
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?
There is no guidance on when to use crop_canvas versus related tools such as resize_canvas, move_region, or copy_region. No when-to-use or when-not-to-use context is provided, leaving the agent to infer the use case from the tool name alone.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.