tap

Does 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 does not disclose that tapping mutates UI state, whether it waits for settle, what observe mode defaults to, how multi-device serial selection works, or what happens when multiple elements match; the schema covers some of this but the natural-language description adds almost nothing.

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 front-loaded sentence that names the action and its two targeting approaches with no wasted words. It is efficiently sized for an agent scanning tool descriptions.

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 10-parameter interaction tool with no annotations and no output schema, the description is too sparse. It omits behavioral context about device selection, observation defaults, settling, match resolution, and side effects, leaving the agent to infer important interaction semantics from the schema alone.

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 90%, so parameters such as observe, settle_ms, exact, occurrence, and serial are already well documented in the schema. The description repeats the targeting modes (index, text, id, x/y) but adds no meaning beyond what the schema provides, so the baseline of 3 applies.

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 and resource (tap an element or screen point) and names the targeting modes (index, text, id, x/y). It is clearly distinguishable from long_press and swipe by virtue of being a tap, but it does not explicitly call out those sibling boundaries.

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 lists possible targeting modes but gives no guidance on when to use tap versus long_press, swipe, or scroll, nor whether get_ui should be called first to obtain an element ref. It provides no exclusions or prerequisites.

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