android_scroll

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

No annotations are present, so the description carries the full burden. It adds the direction semantics ('down' reveals content below; 'up' reveals content above), which is helpful and beyond the schema. However, it does not disclose any other behavioral traits such as animation, failure modes, or interactions with the amount parameter, though these may be less critical for a scroll action.

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, clear sentence with no wasted words. It focuses on the direction parameter, which is the core input, and is appropriately front-loaded.

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?

Considering the tool's simplicity, the description covers the basic action and direction semantics. However, it omits any differentiation from android_swipe and does not mention how the scroll relates to the current screen position (e.g., relative vs absolute). Given the tool has multiple siblings, this is a notable gap that affects completeness.

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 schema already documents all three parameters with 100% coverage, so the description's role is minimal. It mentions 'direction' and repeats its meaning, but adds no extra detail about 'amount' or 'deviceId' beyond what the schema provides. This meets the baseline expectation, but does not elevate it.

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 the screen in a specified direction (up, down, left, right).' It identifies the resource (screen) and the direction parameter, making the purpose evident. However, it does not differentiate from the sibling tool 'android_swipe,' so an agent might not know when to pick one over the other.

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?

No guidance is provided about when to use this tool versus alternatives like android_swipe or when scroll is appropriate. The description only states what it does, not the context or exclusions, leaving the agent to infer usage.

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