tap

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

No annotations exist, so the description carries the full disclosure burden. It reveals the coordinate convention (fractions, origin top-left) but says nothing about post-tap waiting behavior, which the presence of settle/timeout/stable_for/wait_change suggests is configurable and important for correctness.

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 short sentences, front-loaded with the action, then the coordinate convention, then the alternative-tool pointer. Nothing is padded.

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 six-parameter tool with no annotations and no output schema, the description covers the mandatory coordinates but leaves the timing/settling parameters and the return behavior unexplained. Adequate to call it, not adequate to tune it.

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 coverage is 50%: x/y are described only as 'x'/'y' in the schema, so the description's 'fractions of the screen, 0,0 top left' is genuinely additive. But timeout, stable_for, and wait_change are undocumented in both the schema and the description, leaving half the parameters opaque.

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 action ('Tap') on an implicit resource (the screen at coordinates) and adds the coordinate system. It does not differentiate from sibling tap_px or tap_css, which are the closest competitors, so it falls short of a 5.

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?

'For a page element use tap_element' explicitly routes one common case to a sibling. However, no guidance is given for tap_px (pixel coordinates) or tap_css, leaving the agent to infer when normalized fractions are preferable to pixel values.

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