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

The description discloses that no browser is launched, but it does not explain what network requests are made, whether the URL is fetched, what side effects occur, or what the return value means. Many parameters are described as 'discarded', which is unusual and not fully explained.

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 short and uses only two sentences, making it highly concise. It avoids unnecessary 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?

The description does not explain the role of the nine parameters, the expected output, or the tool's relationship to sibling tools. Given the large parameter set and no output schema, the context is severely 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?

The schema has 100% parameter descriptions, but they are mismatched with the tool's purpose (e.g., 'url' is described as 'normalize or cite', and unrelated parameters like 'ref', 'city', 'zone' are included). This adds confusion rather than clarity and fails to explain how each parameter relates to checking a URL.

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?

Description states a clear action ('check whether a URL can be opened') but does not distinguish this from sibling tools like 'browser-url-ok' or 'fetch-status' beyond a brief note about not launching a browser. The meaning of 'can be opened' is ambiguous.

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?

No guidance is provided about when to use this tool instead of alternatives. The description lacks any conditions, contexts, or comparisons to sibling tools.

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