Simulate a touch drag gesture on an Android device from one screen coordinate to another over a specified duration for navigation and app interaction via ADB.
Swipe from (x1,y1) to (x2,y2) over ms milliseconds
| Name | Required | Description | Default |
|---|---|---|---|
| ms | No | ||
| x1 | Yes | ||
| x2 | Yes | ||
| y1 | Yes | ||
| y2 | Yes | ||
| serial | No | Device serial (optional; defaults to first ADB_SERIAL entry or the only 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. It discloses that the gesture takes ms milliseconds, but says nothing about whether the call blocks until completion, how duration influences fling/scroll momentum, what happens with out-of-bounds coordinates, or what is returned.
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?
A single tight sentence that front-loads the gesture and parameter mapping with zero filler. It is arguably under-specified rather than verbose, which is not a conciseness failure.
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 6-parameter device-input tool with no annotations and no output schema, the description leaves the coordinate system, timing behavior, error cases, and return behavior entirely to guesswork. Only the most literal parameter mapping is covered.
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 description coverage is only 17% (just serial), but the description compensates by naming x1,y1 as the start point, x2,y2 as the end point, and ms as the duration. It still omits coordinate units, the valid range for coordinates, and that ms defaults to 300 with a 1-10000 bound.
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?
States a specific verb (swipe) and resource (a gesture between two coordinates) with the duration parameter folded in. It is distinguishable from siblings like tap and long_press, though it never names them, and the coordinate space (pixels vs normalized) is left unstated.
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 prefer swipe over tap, long_press, or a sequence of taps, nor any prerequisite or context about the target screen state. The agent must infer usage 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.