scroll

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

No annotations are provided, so the description carries the full burden. It discloses the key behavioral nuance (direction means where to look, not finger movement) and the distance semantics, but it does not mention error handling, what happens when scrolling is impossible, or side effects beyond the scroll itself. The output schema exists but is not described in the description, so return behavior is left to the schema.

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 well-structured docstring with a concise intro and a bulleted Args section. Every sentence earns its place, and the most critical clarification (direction semantics) is front-loaded. No redundancy or 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 scroll tool, the description covers the parameters thoroughly and the presence of an output schema covers return values. It lacks edge-case details (e.g., what happens when reaching the end of scrollable content or invalid targets), but these are minor and likely inferable from the tool's purpose. Overall, it is sufficiently complete for an agent to call it correctly.

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?

Although schema coverage is 100%, the description adds substantial value: it explains that 'down' reveals content further down, clarifies 'distance' options (small/page/large), and specifies that 'target' is an optional number or label. This goes beyond the schema's terse descriptions, especially clarifying direction semantics, which is often misunderstood.

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 states the action (scroll) and the resource (content on screen), and it immediately clarifies the direction semantics ('where you want to look, not which way the finger moves'), which distinguishes it from gesture-based tools like swipe. The purpose is specific and unambiguous.

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 provides detailed guidance on parameter usage (direction, distance, target) and implicitly explains when to use it by contrasting with other tools, but it does not explicitly name alternatives or state when not to use it. It is clear enough for an agent to select it for scrolling, though explicit exclusions would improve it.

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