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

Annotations already declare readOnlyHint=true, openWorldHint=true, and destructiveHint=false, but the description adds substantial behavioral detail beyond that: discovery order, reading index files one level deep with a 20-child cap, HEAD-then-GET sampling, and specific flags for missing sitemaps, robots.txt gaps, URL limits, and host mismatches.

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 before the operational details, and every clause contributes useful information. It is dense as a single long sentence and could be more scannable, but it avoids waste.

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?

There is no output schema, so the description must explain return values; it does so at a high level by describing URL counts per file and host, lastmod summaries, non-200 sample counts, and flags. Exact output shape and auth/rate-limit behavior are not covered, keeping it below 5.

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 url and sample parameters are already documented in the schema. The description confirms sampling behavior but does not add syntax, default, or max details beyond what the schema provides, so the baseline 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 uses a specific verb and resource: 'Check a site's sitemaps.' It then enumerates the discovery sources and checks performed, making it clearly distinct from sibling tools like check_headers or check_page_meta.

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 purpose implies when to use it, but there is no explicit guidance about when to choose this tool over alternatives such as check_headers or check_page_meta, nor any stated exclusions. Usage is reasonably inferred from the resource but not directly taught.

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