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

No annotations exist, so the description carries the full burden. It usefully discloses where URLs come from and what metadata accompanies them (lastmod/changefreq/priority), but says nothing about network fetching, behavior when robots.txt is missing or a sitemap is unreachable, or whether results are truncated by the limits.

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 dense sentence with the resource and its sources front-loaded and the optional filter trailing. Every clause (robots.txt lines, nested indexes, text sitemaps, returned fields) carries distinct information.

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?

Good coverage of what is listed and what fields come back, which partly substitutes for the absent output schema. However, for a 4-parameter network-fetching tool with no annotations, the missing semantics for limit/max_sitemaps and the lack of failure/truncation behavior leave real gaps.

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 50%: url and since are documented in the schema, and the description only restates the 'since' filter. The two undocumented parameters, limit (max 5000) and max_sitemaps (max 10), get no explanation anywhere — an agent cannot tell whether limit truncates per sitemap or overall, or how nested index traversal is capped.

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 and resource ('List a site's URLs from its sitemaps') and even enumerates the discovery sources it follows (robots.txt Sitemap: lines, nested indexes, text sitemaps). An agent can tell this apart from page_to_json or site_audit, but the description never names those siblings to make the distinction explicit.

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 only implied by the resource scope: use this when you want URLs discovered via sitemaps. There is no guidance on when to prefer site_audit or a crawl, and no stated preconditions (e.g. site must publish a robots.txt or sitemap).

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