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

Annotations already declare readOnly, idempotent, openWorld, and non-destructive, so the safety profile is covered. The description adds genuinely new behavior: a single page fetch, no crawling, and links returned "as published, not their fetched status" — an important caveat about result freshness that annotations cannot express.

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?

Front-loaded with the user-facing query phrasings, then the mechanism, then the limits — good ordering with no filler. The three quoted phrasings are mildly redundant but earn their place for intent matching.

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?

No output schema exists, and the description compensates by describing the return (the URLs the page links to, unvalidated). What it omits — rate limits, error behavior on unreachable pages, result volume/pagination — is minor for a read-only, idempotent tool.

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?

With one parameter at 100% schema coverage, the schema already documents `target` fully (full URL including scheme). The description adds no format or constraint detail beyond that, so the baseline 3 applies.

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 concrete verb and resource: fetch one web page and return the URLs it links to. The quoted user phrasings ("outbound links on a page", "extract every link from [URL]") make the intent unmistakable and distinguish it from crawling or search siblings.

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?

Gives clear usage intent ("Use to map a site section or find outbound references") and an explicit exclusion ("One page only — it does not crawl"). It does not name a sibling alternative such as search_within or scan_dependency, so routing between near-neighbors still requires inference.

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