Click-By-Label

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

Since no annotations are provided, the description carries the burden of behavioral disclosure. It does reveal that coordinates are resolved internally and that this is safer than Click-Tool. But it does not mention the reliance on fresh State-Tool output, the mutating nature of the tap, or possible failure modes.

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 two sentences with no filler. It front-loads the core action and source of the label, then provides the safety comparison to the alternative without redundancy.

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 simple one-parameter tool, the description covers the source of the label, the alternative tool, and the safety benefit. It is mostly complete, though it could mention the need to call State-Tool first more explicitly and clarify what happens if the label is stale or invalid.

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 0%, and the schema only shows that 'label' is an integer. The description adds crucial meaning by explaining that label is an index from the most recent State-Tool output. It still leaves minor details unspecified, such as whether the index is zero-based.

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 a specific action ('Tap'), a resource ('an element'), and the distinguishing mechanism ('label index from the most recent State-Tool output'). It also explicitly contrasts itself with Click-Tool, so an agent can differentiate it from sibling tools.

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 gives a clear prerequisite: use a label from the most recent State-Tool output. It also names Click-Tool as the alternative and explains why this tool may be safer. However, it does not explicitly state when to prefer Click-Tool instead, such as when coordinates are the only available reference.

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