fetch_sitemap

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

With no annotations provided, the description carries the behavioral burden. It discloses that the tool follows sitemap-index nesting and returns every declared page URL, which are meaningful behavioral details beyond what the schema shows. It does not mention failure modes or network behavior, but for a straightforward fetch-and-parse read operation this is reasonably transparent.

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 sentences with no filler. The first sentence states what the tool does and the second gives usage guidance. The most important behavioral details are front-loaded.

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 one-parameter tool with an output schema present, the description is complete: it explains what the tool does, how it behaves with index nesting, what it returns, and when to call it. Nothing essential for correct invocation is missing.

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?

The schema has 0% description coverage, so the description must compensate. It indirectly clarifies that sitemap_url should point to a sitemap.xml and that index nesting is followed, but it does not explicitly describe the URL format, required scheme, or example values. Because the single parameter is highly self-evident from the tool name and description, this is adequate but not enriched.

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 action: 'Fetch and parse a sitemap.xml' and the specific outcome: 'return every page URL it declares.' It also mentions the non-obvious behavior of following sitemap-index nesting, which distinguishes this from simply fetching one XML file. The phrase 'Call this first when auditing a site' also separates it from siblings like audit_urls and sitemap_coverage.

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 provides explicit guidance: 'Call this first when auditing a site you do not have a URL list for.' This clearly tells an agent when to use it. However, it does not name alternative tools or explicitly state when not to use it, so it falls just short of full usage differentiation.

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