Scroll Down

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

With no annotations, the description carries the behavioral burden. It discloses that the action reveals lower content and that amount is a proportional fraction, but it does not clarify whether this is a gesture simulation, how region is defined, or what happens at scroll limits. Some transparency is present, but meaningful gaps remain.

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 compact, front-loaded sentence with no filler. The purpose and the meaning of the key parameter are both stated efficiently.

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 tool with no annotations and several scroll-related siblings, this is too thin. The term 'region' is vague, there is no guidance about targeting a specific UI element with som_id, and it does not clarify interaction with device state. The presence of an output schema covers return values, but the calling context remains under-specified.

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?

The description adds real semantics for amount by defining it as a fraction of the region, which the schema does not provide. However, with 0% schema description coverage, device and som_id remain undocumented and their roles in the scroll are not explained. The most important parameter is covered, but the auxiliary parameters are left to inference.

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 clear action ('Scroll the content down') and explains the intent ('reveal what is below'), making the direction unambiguous. It is differentiated from scroll_up/left/right by direction, but it does not explicitly distinguish itself from the more general scroll_to, so it falls just short of a 5.

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 gives no guidance on when to use this tool versus the many scroll/swipe siblings. It implies use when content below is hidden, but it never mentions alternatives, nested-element scrolling, or when to set som_id for a specific region.

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