Tap Node

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

With no annotations, the description bears full behavioral burden. It reveals only that the node index comes from the last `look` on the device, but says nothing about side effects, error conditions (e.g., no prior look, invalid index), permissions, or what happens after the tap. This is a significant gap for an interactive UI tool.

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 with no filler. It communicates the action, the target, and the source in minimal words, which is exactly what conciseness should achieve.

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 need not be explained. The core operation is clear enough for an agent that already knows what a `look` result contains, but the description leaves the `device` parameter undefined and does not clarify what a 'node' is or what happens when no prior look exists. It is minimally adequate for a simple tool but has clear gaps.

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. It hints at the `index` parameter ('node #index') and the `device` parameter ('on this device'), but does not explain the expected format of `device`, the meaning of a null default, or exactly what range or source of node indices are valid. The added meaning is marginal.

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 ('Tap'), resource ('node #index'), and source ('from the last `look` on this device'), which clearly identifies the operation and ties it to a sibling tool's output. It does not explicitly distinguish itself from `tap` or `tap_anchor`, but the node-index reference is specific enough for an agent to select it correctly in most cases.

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 implies a prerequisite (a prior `look` must have been run) but offers no explicit guidance on when to use this tool versus `tap`, `tap_anchor`, or `screenshot`. There are no stated alternatives, exclusions, or conditions beyond the implicit reliance on the last look.

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