Double Tap Screen

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

The description only restates the action and adds no behavioral context beyond what annotations already indicate (openWorldHint=true suggests external side effects). It does not mention potential impacts like triggering app interactions, coordinate system considerations, or device requirements beyond the schema. No contradiction exists, but the description adds no value beyond the annotations.

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 concise sentence with no redundant information. It is front-loaded with the core action and location, and every word serves a purpose. This is exemplary conciseness.

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 gesture tool with full schema coverage and annotations that indicate non-read-only, non-destructive, open-world behavior, the description is adequate. The only missing context is usage guidance, which is a separate dimension. The tool's simplicity and complete schema make this description sufficiently complete for correct invocation.

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 covers all three parameters (device, x, y) with descriptions, achieving 100% coverage. The tool description adds no additional parameter information, so the baseline 3 applies. The parameters are already well-documented in the schema.

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 'Double-tap on the screen at given x,y coordinates' clearly states the action (double-tap) and the resource (screen at coordinates), and it distinguishes this from sibling tools like single click, long press, and swipe by specifying the gesture type. The verb and resource are 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?

No guidance is provided on when to use this tool versus alternatives such as mobile_click_on_screen_at_coordinates or mobile_long_press_on_screen_at_coordinates. The agent is left to infer usage from the gesture name, with no explicit conditions or exclusions.

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