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

Annotations already establish read-only, idempotent, non-destructive behavior. The description adds value by revealing that the page is rendered and that every matched element returns text, innerHTML, attributes, and geometry, which is not visible from the schema or annotations alone.

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: two sentences plus one illustrative example. The key purpose and return behavior are front-loaded, and the example shows the required call shape without excessive wordiness.

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 compensates by describing returned element data and providing a complete invocation example. It does not address edge cases like empty results or errors, but the essential call contract is sufficiently covered.

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 all parameters are already documented. The description's example echoes the schema but does not add meaningful parameter semantics beyond what is already structured, so the baseline score of 3 is appropriate.

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 identifies the verb ('Extract'), the resource ('a rendered page'), and the mechanism ('CSS selectors'), and it enumerates the return fields. It does not explicitly distinguish itself from sibling tools like browserless_smart_scrape or browserless_content, relying on the 'CSS selectors' detail to imply differentiation.

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?

No guidance is given about when to use this tool versus its siblings. The example demonstrates how to invoke it, but it does not state when to prefer this over browserless_smart_scrape, browserless_content, or browserless_screenshot, and no exclusions or alternative recommendations are provided.

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