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

With no annotations, the description carries the burden and does well: it discloses deduplication, default and max limit values, exact price ($0.001 USDC on Base via x402), that charges occur only on success, and the failure/payment-requirement behavior. What it omits is whether the page is fetched once (no recursion) and any rate-limit or auth context beyond payment.

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 dense sentences with the output behavior front-loaded and pricing/retry mechanics trailing; no filler or restatement of the tool name.

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?

For a two-parameter tool with no output schema, the description covers what is returned, the cap semantics, and the entire paid-call lifecycle. The only gap is the shape of the result (list of absolute URLs vs. relative) and confirmation that no recursion occurs.

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 50% (only url is documented), but the description compensates by explaining that limit is a dedupe cap with default 200 and max 1000, and that url refers to a page or site root whose links and sitemap are harvested. It adds real meaning beyond the schema.

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 states a concrete resource and scope: same-site URLs on the page plus sitemap URLs from robots.txt or /sitemap.xml, deduped and capped. That is specific enough to distinguish it from a full page-content fetcher like scrape, though it never names the siblings explicitly.

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?

It clearly explains the payment retry protocol (unpaid calls return x402 requirements, retry with _meta["x402/payment"]), which is actionable usage guidance. However, it gives no guidance on when to choose map over scrape or scrape_lite, which is the main selection decision an agent faces.

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