Find Android UI nodes

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already cover readOnly, idempotent, non-destructive, non-open-world, so the safety profile is set. The description adds non-obvious behavior: matches carry a ref (@nN) and a tap point that compensates for clickable containers and overlays, plus the important staleness caveat that it invalidates prior refs. This is genuine value beyond 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?

Three tight sentences, front-loaded with what is matched, followed by result shape and downstream handoff. No filler; every sentence earns its place.

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?

An output schema exists, so return values needn't be exhaustively explained, yet the description usefully notes what each match contains. Combined with annotation coverage and the ref-lifecycle note, it is largely complete; only the 'exact' parameter and explicit sibling routing are missing.

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?

With only 33% schema coverage, three of the search parameters (text, resourceId, contentDescription) are named in prose but receive no syntax or matching-format detail, and 'exact' is omitted entirely from both schema and description. The description maps loosely to the parameters but does not compensate for the coverage gap.

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 (Find) and resource (accessibility nodes) and enumerates the three matching criteria (text, content description, resource ID). It is clear, but sibling differentiation is only implicit — it hints at a relationship to the UI read via 'previous UI read' without naming mobile_ui_snapshot or explaining how finding differs from snapshotting.

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?

Gives workflow sequencing ('Pass ref to mobile_input_tap') and lifecycle guidance ('replaces refs from the previous UI read'), which is helpful. However, it never states when to use this over mobile_ui_snapshot or mobile_ui_wait, nor any when-not conditions, so usage is only implied.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.