Performs a rapid two-tap gesture at specified screen coordinates on a connected iPhone or iPad to trigger UI actions during app testing.
Double-tap at coordinates (points).
| Name | Required | Description | Default |
|---|---|---|---|
| x | Yes | Points from left | |
| y | Yes | Points from top | |
| device | No | Device UDID or name substring. Defaults to the select_device choice, then IOS_DEVICE_MCP_DEVICE, else the single USB-connected device. |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full behavioral burden, but it only states the gesture and coordinate unit. It omits effects (e.g., zoom/selection), timing requirements, error behavior, and whether the device parameter changes targeting.
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 definition is a single front-loaded sentence with zero wasted words. It is appropriately sized for a simple gesture 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?
The tool is simple and the schema fully documents its three parameters, so the description need not explain return values. However, with no annotations and no usage guidance, the description leaves gaps around when to choose this gesture and what the interaction does.
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?
Schema coverage is 100%, including detailed x/y and device descriptions, so the schema already explains all parameters. The description reinforces the coordinate unit ('points') but adds no meaning beyond what the schema provides.
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 specific action (double-tap) at a specific target (coordinates in points), which distinguishes it from tap and tap_element. It does not explicitly name or differentiate from siblings, but the purpose is clear.
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?
There is no guidance on when to use double_tap instead of tap, tap_element, long_press, or other interaction tools. The agent must infer the choice entirely from the tool name.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.