resize_canvas

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

No annotations are supplied, so the description carries the full burden. It does useful work by naming all nine anchor values, the fill default, the target image index, and the return shape, but it never says whether the operation is undoable, what happens to layers/selection bounds, or whether existing content is clipped when shrinking - the key risk for a canvas mutation.

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?

One framing sentence followed by a tight parameter list and a return summary. It is front-loaded with the operative constraint and every line carries information the schema does not already contain, such as the anchor enumeration and pixel units.

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 mutation tool with zero annotation coverage and no output schema, the parameter documentation is thorough and the return shape is spelled out. What is missing is the side-effect profile - clipping behavior on shrink, effect on layers and selection, and undoability - which an agent needs before invoking a destructive canvas operation.

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 schema has no enum on anchor, so the description is the only source of meaning. It defines width/height units in pixels, enumerates all valid anchor strings with the default, explains fill as a CSS color or "transparent", and gives image_index a default and target semantics - fully compensating for the schema gap.

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?

"Resize the image canvas without scaling the content" states a specific verb and resource and adds the scope qualifier that separates it from scale_image and scale_to_fit, which are the obvious confusable siblings here. An agent can pick between canvas resize and image scaling on this sentence alone.

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 phrase "without scaling the content" implies the canvas-vs-scale distinction, but no sibling is named and there is no explicit when-to-use or when-not guidance (e.g. versus crop_to_rect or batch_resize). Usage is inferable rather than stated.

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