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

Beyond the readOnlyHint and openWorldHint annotations, the description discloses important behavior: JavaScript is not executed, navigation/ads/cookie banners/scripts are removed, the call is paid via x402 at $0.003 per successful call, and output may be truncated. It also lists the return envelope and extraction metadata, giving the agent strong operational context.

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 purpose is front-loaded and the description is dense with useful information, not filler. The final return-field list is long, but because there is no output schema it earns its place; the description could be slightly more structured for readability.

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?

The description is largely complete for a no-output-schema tool: it explains the extraction behavior, payment model, JavaScript limitation, truncation, and the shape of the returned JSON. It still leaves sibling-tool routing and error/failed-call behavior implicit, which keeps it short of fully complete.

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%, and the schema already explains url constraints, includeLinks, and maxCharacters in detail. The description does not add meaningful parameter-level semantics beyond what the schema provides, 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 states the specific action and resource: fetch a public web page and return its main content as clean Markdown. It also names the extracted artifacts (title, description, headings, metadata), so the tool’s purpose is unambiguous. It does not, however, distinguish this tool from sibling extract_url_structured or inspect_url.

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?

Usage is implied by 'Fetch a public web page' and the note that it does not execute JavaScript, which helps an agent understand suitable pages. The description does not explicitly say when to use this versus extract_url_structured or inspect_url, nor does it state exclusions beyond public/no-JS pages.

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