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

Annotations already declare readOnly=false, destructive=false, idempotent=false, and openWorld=false, so the safety profile is covered. The description adds useful behavioral context by saying the result is reflowed onto new artboards, which suggests a non-destructive creation operation, but it does not clarify whether the source artboard changes, how device selection works, or what 'reflowed' concretely means.

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 front-loaded sentence with no filler or repetition. Its brevity contributes to completeness gaps, but as a conciseness and structure matter it is efficient.

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 mutation tool that creates new artboards from an existing screen, the description is too thin given 0% schema coverage and no output schema. It does not explain the required input artboard, the difference between sizes and devices, or what the resulting artboards contain.

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% for all three parameters, so the description must carry the burden. It vaguely gestures at devices with 'other phones and foldables' and at output artboards, but it never explains the required artboard identifier, the sizes array with name/width/height, or how devices differs from sizes.

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 states a specific action and resource: it shows a phone screen on other phones and foldables, reflowed, on new artboards. That distinguishes it from plain resize or add_artboard siblings by emphasizing reflowed responsive variants on newly created artboards. The verb 'show' is a little vague, but the overall purpose is clear.

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 description implies when to use it: when you want to see a phone screen adapted to other phones and foldables. It does not explicitly say when not to use it, what prerequisites are required, or which sibling tools to use instead, such as resize or export_artboard.

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