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

The description explicitly discloses that no browser is launched, and parameter descriptions further state side effects such as 'discarded after the shape check' and 'no disk access', providing meaningful behavioral transparency despite no annotations.

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 extremely concise: two short sentences with no filler, each adding distinct information about the purpose and the no-browser caveat.

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 is too sparse for a 9-parameter tool with no output schema and no annotations; it fails to explain the multi-purpose parameters, expected return behavior, or how it differs from the many sibling validators.

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 description, the descriptions do not explain how values like ref, city, json, path, zone, and query relate to checking whether a URL can be opened; the high schema coverage does not resolve the semantic mismatch.

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 action (check whether a URL can be opened) and a key caveat (no browser launched), but the schema includes nine unrelated optional parameters (ref, city, feed, json, path, zone, query), so the actual scope 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 for when to use this tool instead of siblings like playwright-url-ok, fetch-status, normalize-url, or web-fetch; the only hint is the negative statement that no browser is launched.

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