find_by_label

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

No annotations are provided, so the description carries the disclosure burden. It does disclose that the operation returns both a ref and a match count, which is useful behavioral information. However, it omits what happens on zero matches (e.g., null ref vs. empty result) and gives no details on matching semantics (exact vs. partial, case sensitivity).

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 sentence that front-loads the action and target, then states the return. Every element is informative with no redundancy or filler.

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?

With no output schema, the description adequately states the return value ('ref + how many matched'). The schema covers both parameters. The main gaps are the lack of usage guidance and zero-match behavior, but for a simple find tool with one required parameter, the information is largely sufficient.

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 100%, so the schema already documents both 'label' and 'within' with examples and allowed patterns. The description adds only a parenthetical mention of '<label>' to clarify the label type, which is a minor addition beyond the schema. No further parameter guidance is needed.

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 uses a specific verb ('Find') and a clear resource ('input element') with an explicit matching mechanism ('by its label text (<label>)'). It also states the return value ('ref + how many matched'), which distinguishes it as a lookup rather than a mutation. While it doesn't name sibling tools, the label-text criterion is specific enough to distinguish from find_by_text and find_by_placeholder.

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 use case (locating an input by its label) but provides no explicit guidance on when to choose this tool over alternatives like find_by_placeholder or find_by_text. No exclusions, prerequisites, or alternative recommendations are given, leaving the agent to infer routing from the name and label reference.

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