tap

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

No annotations are provided, so the description carries the full burden. It doesn't disclose whether tapping requires a leased phone, whether coordinate units are pixels or normalized, or what the response contains. It only hints at a dependency on 'ui' centers, leaving most behavioral context unstated.

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 a single short sentence with no waste and is front-loaded with the core action. It could be more informative, but it is appropriately sized for a simple tool.

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?

Given there are no annotations, an output schema exists, and three required parameters, the description is insufficient. It omits the phone parameter's role, coordinate semantics, and any preconditions like leasing a device. The cross-reference to 'ui' is helpful but not enough.

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 0%, so the description must compensate for three parameters. It only gives meaning to x and y indirectly through 'a point (use the centers from the ui tool)'. It says nothing about the required 'phone' parameter, which is likely critical for routing the tap to a specific device.

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 action (tap) on a specific target (a point), and cross-references the 'ui' sibling for coordinates. It's clear what the tool does, though it doesn't explicitly differentiate from swipe or key beyond the verb.

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?

It implies usage when you need to tap a point and directs to the 'ui' tool for centers, but it doesn't state when to use tap versus swipe or type. No exclusions or alternatives are named.

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