Mouse wheel

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

Annotations cover the safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false), so the bar is lower. The description usefully adds the direction convention and that NUI lists are the responsive target, but says nothing about focus requirements, rate limits, or repeat behavior.

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 short sentences with the direction convention front-loaded and zero 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 simple one-parameter input tool with annotations covering safety and no output schema, the definition covers direction and target context adequately. Remaining gaps (focus/prerequisite conditions) are minor.

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% and the single 'amount' parameter only exposes a -50..50 range with no description. The description supplies the crucial missing semantics ('positive = up'), which is exactly what the schema omits, though it doesn't state units or step granularity.

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 ('Scroll') and resource ('the wheel'), and adds sign semantics ('positive = up'). It is distinguishable from siblings like mouse_move and click, though it doesn't 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?

The clause 'NUI lists respond to it' implies a usage context but gives no when-to-use vs alternatives guidance, no prerequisite such as needing an open NUI or focused window, and no exclusions.

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