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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safe read-only and external-network nature is covered. The description adds that it follows sitemap indexes and operates on public sitemaps, which is useful context, but it omits rate limits, error behavior, and what is returned. With annotations carrying the safety profile, a 3 is appropriate.

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 sentence that is front-loaded with the core action and adds the index-following behavior in a parenthetical. There is no wasted wording, and it is appropriately sized for a simple two-parameter tool.

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 low-complexity extraction tool with 100% schema coverage and read-only annotations, the definition covers the core operation but omits the return format or shape. Since there is no output schema, the description could say more about what an agent receives, leaving a modest gap.

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 the schema already documents both the url and max parameters in detail. The description adds no parameter-specific meaning beyond what the schema provides, making the baseline score of 3 correct.

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 (Extract), resource (URLs), and source (public sitemap), plus a non-obvious behavior (follows sitemap indexes). It is clear enough for an agent to distinguish from the calculator and audit siblings, though it does not explicitly name alternatives because none exist.

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?

The description provides no when-to-use or when-not-to-use guidance. It implies the tool is for public sitemaps, but does not say when to choose it over crawling or other discovery methods, nor does it mention prerequisites like having a sitemap URL.

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