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

With no annotations, the description carries the burden of behavioral disclosure, but it only offers the non-storage guarantee and the output fields. It does not disclose whether the URL is fetched, what side effects occur, or what failure modes exist, leaving important behavior implicit.

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 description is two short sentences, front-loaded with the primary result and followed by a useful privacy/behavior note. Every word earns its place.

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 tool with nine optional parameters and no output schema or annotations, this description is too thin: it does not explain which parameter to supply, how the parameters relate to the stated URL behavior, or what an agent should expect in the response. Schema descriptions cover parameter names, but the overall calling context is incomplete.

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 baseline is 3; the description adds no parameter-level meaning. It only names the URL resource, which aligns with the 'url' parameter but ignores the other eight optional parameters.

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 states a specific verb ('Return') and resource (URL), and lists three concrete outputs (host, scheme, HTTP status), so an agent can tell what the tool does. It does not explicitly contrast it with sibling tools like normalize-url or fetch-status, so it misses the top score.

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?

There is no guidance about when to choose citation over the many sibling URL/status tools, nor any caveat about prerequisites. 'Page content is not stored' hints at a non-retention use case but does not state when this tool is preferred.

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