count

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

No annotations are provided, so the description carries the full behavioral burden. It does not state the return type, what happens when zero elements match (0 vs error), whether it waits for elements, or how request_timeout affects a failed match.

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. The brevity is efficient, though it borders on under-specification for a tool in a large browser-automation family.

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 annotations and no output schema, the description should explain the return value and edge-case behavior. Instead it leaves the counting domain, return type, zero-match semantics, and timing behavior entirely unstated.

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 only 67%, and the undocumented parameter is the required selector. The description restates that a selector is used but gives no syntax guidance (CSS vs XPath), so it adds almost nothing beyond the schema field name.

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 names a clear operation and resource: it returns the number of elements matching a selector. That is specific enough to act on, but it never distinguishes itself from siblings such as find or snapshot, which also query the DOM and could plausibly expose counts.

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?

There is no guidance on when to prefer count over find, snapshot, or attr, and no mention of prerequisites such as a loaded page or a prior navigation. The agent must infer the entire usage context from the name and sibling list.

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