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

It transparently states that no browser is launched, which is one behavioral constraint, but it does not describe what the tool actually does with the URL, whether it makes network requests, what checks are performed, what it returns, or whether it has side effects. With no annotations to fill the gap, most behavior remains hidden.

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 very brief and front-loaded: the first sentence states the main purpose, and the second adds a meaningful constraint. There is no filler or redundant wording, so it is concise even though it lacks important detail.

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 9 parameters, no output schema, no annotations, and no examples, this description does not provide enough context for correct use. It fails to explain which parameter is the target URL, what the tool returns, how to handle errors, or how it relates to the sibling tools.

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 every parameter has a type and a short description, most descriptions are unrelated to the stated purpose and several (ref, city, json, query, path, zone) are explicitly marked as discarded. The 'url' parameter is described as 'normalize or cite' rather than being checked for openability, making the parameter semantics contradictory and unhelpful.

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 clear core action: checking whether a URL can be opened, and adds a useful negative constraint about not launching a browser. However, it does not differentiate this from sibling tools like browser-url-ok, fetch-status, or web-fetch, and the large set of unrelated parameters muddies the intended purpose.

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?

The description gives no indication of when to use this tool versus the many sibling URL/network tools, no exclusions, and no selection criteria for parameters. A user cannot determine whether to call this instead of browser-url-ok, fetch-status, or web-fetch.

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