Captures the current Android screen's foreground app and visible UI elements—text, descriptions, IDs, bounds, and flags—so agents can inspect and act on the interface.
Describe the current screen: foreground app and visible elements (text, desc, id, bounds, flags).
| Name | Required | Description | Default |
|---|---|---|---|
| raw | No | Return the raw uiautomator XML instead. | |
| all_nodes | No | Include layout nodes without text/desc that are not clickable. |
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 implies a read-only inspection operation, but does not explicitly state that it has no side effects, what permissions are needed, whether output is truncated for large screens, or how it behaves on inaccessible screens.
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 sentence that is front-loaded with the core action and immediately lists the returned information. There is no filler or redundancy.
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 zero-required-parameter read tool with a fully documented schema, the description is nearly complete: it identifies the resource and lists the main returned fields. It could be stronger by mentioning how it relates to ui_screenshot/ui_find, but the core inspection purpose is clear.
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 100%, so both parameters (raw and all_nodes) are already well documented in the schema. The description does not add parameter-level meaning beyond the schema, which is acceptable given the high coverage baseline.
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: describing the current screen, including foreground app and visible element fields. It is clearly distinct from action siblings like ui_tap or ui_scroll, though it does not explicitly contrast itself with ui_screenshot or ui_find.
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 this tool versus alternatives such as ui_screenshot or ui_find. The agent must infer that this is for semantic/structural screen inspection rather than image capture or element search.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.