Double tap at a precise location on an Android screen using absolute pixels or 0-1000 normalized coordinates to trigger actions or select elements.
Double tap a point using either absolute pixels or normalized 0..1000 coordinates.
| Name | Required | Description | Default |
|---|---|---|---|
| x | No | ||
| y | No | ||
| nx | No | ||
| ny | No |
Changes observed during successful MCP inspections.
v0.8.1Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already mark this as destructive and non-read-only, so the safety profile is covered. The description adds no extra behavioral context such as possible side effects, prerequisites, or interaction with app state, but it also does not contradict 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 succinct sentence with no filler. It front-loads the action and immediately explains the coordinate options, making it easy to parse and act on.
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, but all four parameters are optional and the description says 'either/or' without clarifying whether x/y and nx/ny are mutually exclusive, whether one set is required, or what happens if both are provided. This ambiguity leaves a meaningful gap 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 only provides names and numeric ranges, so the description adds valuable meaning by clarifying that x/y are absolute pixel coordinates and nx/ny are normalized 0..1000 coordinates. This is exactly the semantic information an agent needs beyond the raw 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 uses a specific action verb ('double tap') with a clear target ('a point') and explicitly names the two coordinate systems supported. This cleanly distinguishes it from sibling gesture tools like android_tap, android_long_press, and android_swipe.
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?
Usage is implied: use this tool when a double-tap gesture is needed. However, there is no explicit guidance on when to prefer this over android_tap or other gesture tools, nor any exclusion criteria or context such as 'for double-click actions, use this.'
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.