Find on the page

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

Goes well beyond the readOnly/openWorld annotations by disclosing result caps (up to 15 matches), ordering (nearest first), and the concrete return shape (a view line with its ref and whether it is in view or how many pixels above/below), plus that the ref is directly actionable. That is exactly the behavioral context annotations cannot carry.

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?

Two sentences, front-loaded with the capability, then the payoff. Dense but not padded; the second sentence doubles as guidance rather than description, which is still earning its place.

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 takes responsibility for explaining what comes back — the view line, ref, and position relative to the viewport — and how to act on it. Nothing needed to call or interpret the tool correctly is missing.

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 100%, so the baseline is 3, but the description adds real matching semantics the schema does not: all words must be present, any case, matched against name or text. It stops short of saying how multiple-word queries are tokenized or whether partial-word matches count.

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?

States a specific verb (find), resource (elements anywhere on the page, in view or not), and match semantics (name or text containing all words, case-insensitive). An agent can immediately distinguish this from browser_snapshot (full listing) or browser_scroll (positional movement) without opening the schema.

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?

Explicitly contrasts with the alternative: use this to reach something off screen that you can name, instead of scrolling through the page. It gives both the when (item is nameable, off screen) and the when-not (don't scroll to hunt for it).

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