tap_element

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

No annotations are provided, so the description bears full responsibility. It discloses the re-resolution behavior and mentions the return values. However, it does not discuss potential side effects (e.g., triggering navigation, destructive actions), authorization needs, or rate limits. The disclosure is adequate but not comprehensive for a tool that performs an action.

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 concise and well-structured. It starts with the core action, then explains behavior in edge cases, and finally details parameters. Every sentence adds value without redundancy. It is appropriately sized for the tool's complexity.

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 the presence of an output schema (indicated by 'has output schema: true'), the description does not need to detail return values, but it still mentions them. The description covers the main functionality and an important edge case (re-resolution). However, it does not address error conditions or input validation, but overall it is sufficiently complete for an agent to use the tool effectively.

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?

The description explains the purpose of each parameter clearly: 'element' is an element id from a recent screen state with an example, and 'x'/'y' are pixel coordinates used only if not using element. It also states the preferred usage (element over coordinates). Given that schema description coverage is 0%, the description compensates well by adding meaning beyond the schema.

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 clearly states the action ('tap') and the resource ('element'), and explicitly distinguishes between two methods (by id or by raw coordinates). It also mentions what the tool returns (new screen state and log delta). There is no ambiguity given the sibling tools are 'get_logs' and 'get_map', which are clearly different actions.

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 provides context on when re-resolution occurs if the target moved or vanished, which guides the agent on how to handle stale elements. However, it does not explicitly state when to use this tool versus alternatives or specify any prerequisites or constraints. The guidance is helpful but not exhaustive.

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