Swipe between two points

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

With no annotations, the description carries the full burden of behavioral disclosure. It states the action and coordinates but does not mention side effects like scrolling, whether it requires the screen to be on, or how the duration parameter affects the gesture. It is not misleading, but it lacks depth beyond the basic mechanics.

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 sentence with zero redundancy. It front-loads the core action and coordinate context, making it easy to scan. It is appropriately concise for a simple tool.

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 basic gesture tool with no output schema and no annotations, the description covers the essential function and parameters. It lacks minor details like coordinate origin or duration default, but these are either common knowledge or provided in the schema for durationMs. Overall, an agent can correctly call this tool with the given information.

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 embeds the four required parameters (x1, y1, x2, y2) in the action sentence, giving them context as start and end points. However, it does not explain the optional durationMs parameter or the coordinate system's origin (e.g., top-left corner). Given that schema coverage is only 20%, the description should compensate more, but the parameter names and sentence provide some clarity.

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 (swipe) and the resource (coordinates in points). It distinguishes from siblings like tap and tap_normalized by specifying a continuous gesture between two points, and the 'in POINTS' clarifies the coordinate system. This 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 implies when to use the tool (when a swipe gesture is needed) but does not explicitly mention alternatives or exclusion criteria. It does not say 'use tap for discrete taps' or 'use tap_normalized for normalized coordinates,' so the agent must infer the appropriate choice from sibling names. No explicit when-not-to-use guidance is provided.

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