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

With no annotations, the description carries the disclosure burden. It usefully reveals that the response body is discarded and that the tool targets public URLs, implying no auth/private access. It does not mention redirects, timeouts, or rate limits, but it covers the most important unexpected behavior.

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?

Two short sentences with no filler. The main behavior is front-loaded and the body-discard caveat follows immediately.

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?

The tool has nine optional parameters, no output schema, and no annotations, so more context is needed than a one-liner. The description does not resolve the ambiguous schema, explain what the response looks like, or state what happens when non-URL parameters are supplied.

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?

Although schema coverage is 100%, the schema is contradictory and noisy: the url property is described as 'normalize or cite', and seven unrelated optional parameters (city, feed, host, json, path, zone, query) are present. The description does not specify which parameter is the URL to fetch or whether the extraneous parameters are ignored.

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 names a concrete operation (return HTTP status and content type) on a specific resource (public URL), and explicitly says the body is discarded. It does not explicitly differentiate from siblings like fetch-status or browser-url-ok, so it falls just short of a 5.

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 on when to choose this tool over sibling tools such as fetch-status, browser-url-ok, normalize-url, or playwright-url-ok. No alternatives, exclusions, or conditions are mentioned, leaving the agent to infer usage from the one-line purpose.

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