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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description goes beyond them by disclosing the return shape — matching pages with snippets, plus both the read timestamp and the page's claimed last-changed time — which tells the agent how freshness can be judged.

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?

Three short sentences with no filler: purpose first, the alternative second, the return format last. Every sentence carries distinct information an agent can act on.

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?

With no output schema, the description usefully covers the return payload and freshness fields, and it names the multi-topic alternative. The remaining gap is result-count control (max_results) and what happens when nothing matches, which an agent may need before calling.

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 0%, so the description must carry the burden, yet it only implies what 'query' means and says nothing about max_results — no mention of the default of 5, the cap of 10, or the effect on result count. Query syntax and matching behavior are also left unexplained.

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 concrete verbs (discover, search) and names the resource and target site (https://sitemcp.dev/), so it is clearly a site search tool. It is slightly muddled by claiming both URL discovery across the sitemap and query-relevance search, but the sibling differentiation from research_pages keeps it unambiguous.

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 explicitly routes the agent away from this tool when multiple topics are involved: 'For multiple topics use research_pages instead.' That is a real when-not condition with a named alternative, though no other siblings (read_page, list_pages) are addressed.

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