Waits until a specified Android UI element appears by text or ID, or disappears when gone is set, before continuing.
Wait until an element with the given text/id appears (or, with gone=true, disappears).
| Name | Required | Description | Default |
|---|---|---|---|
| id | No | ||
| gone | No | ||
| text | No | ||
| exact | No | ||
| serial | No | adb serial; optional when exactly one device is connected | |
| observe | No | changes | |
| timeout_ms | No |
Changes observed during successful MCP inspections.
v0.1.0Does 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 core wait-for-appear/disappear behavior, but omits critical traits: timeout behavior, default timeout, observe output, exact-match semantics, device-selection via serial, and what happens on timeout.
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 one tight sentence with no filler and the wait condition is front-loaded. It could be slightly more structured by grouping parameter-related behavior, but it is efficiently written.
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 7-parameter tool with no annotations, no output schema, and only 14% schema description coverage, this single sentence is not complete enough. An agent lacks essential details about timeout, observe, exact matching, serial selection, and return behavior.
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 14%, so the description should compensate. It clarifies only text/id targeting and gone=true meaning, while exact, serial, observe, and timeout_ms receive no explanation beyond their bare schema entries.
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 verb and resource: wait for an element identified by text/id, with an optional gone=true inversion. It is clear what the tool does, but it does not explicitly distinguish itself from siblings like get_ui or screenshot.
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 only explains the wait condition. It gives no guidance on when to use this instead of get_ui, screenshot, or other sibling tools, and no exclusions or prerequisites are provided.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.