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

Annotations cover the safety profile (readOnly, openWorld, non-destructive), and the description goes further: no authentication needed, no JavaScript rendering, and precise semantics for the two ambiguous outcomes (not_found = absent from fetched HTML only; indeterminate = source HTML could not be inspected). Those qualifiers materially change how an agent should interpret a result.

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 core action, then constraints, then result semantics. Dense but every clause carries information; the return-field list ('hrefs, resolved URLs, anchor text, rel tokens...') is the only slightly padded portion given an output schema exists.

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?

Covers the operation, its limits, and its ambiguous result states, which is enough for a two-parameter read tool with an output schema. The remaining gap is parameter-level detail (URL format/constraints), which neither the schema nor the description supplies.

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% for both parameters, so the description carries the burden. It implies publishedPageURL is the fetched page and expectedDestinationURL the link sought, and that destination redirects are resolved, but it never states required URL format, HTTPS-only expectations, or the 2048-char bound. Partial compensation, not full.

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 (fetch, check) plus resource (published public HTTPS page HTML) and the exact object of the check (links to an expected public HTTPS destination, including known destination redirects). An agent immediately knows this is a placement-verification tool rather than a crawler, editor, or exchange tool.

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?

Explicit scope boundaries are given via negation: no login required, does not render JavaScript, assess editorial relevance/SEO, edit sites, or settle exchanges. That effectively tells the agent when this tool is the wrong choice, though there is no named alternative (none exists among siblings) and no positive 'use this when...' framing.

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