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

The tool claims 'No browser is launched' but gives no explanation of how it checks openness. Parameter descriptions like 'discarded after the shape check', 'no disk access', and 'length check' suggest behavior not explained in the main description. No annotations are present to clarify side effects or limitations.

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 main description is brief, but the input schema is bloated with nine parameters, most of which appear irrelevant. The structure itself is clean, but the content is confusing and does not support the tool's stated purpose.

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?

There is no output schema, no examples, and no explanation of return values or error behavior. Given the large sibling-tool list and the unusual parameter set, the definition lacks essential context for an agent to invoke it correctly.

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 descriptions cover 100% of parameters, most descriptions are unrelated to the stated purpose. For example, 'city' is a 'weather hint', 'feed' has 'titles discarded', and 'query' is for a 'length check'. The 'url' description says 'normalize or cite' rather than 'check open', creating a severe mismatch between parameters and tool intent.

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 it checks whether a URL can be opened, but the input schema includes many unrelated parameters (ref, city, feed, json, zone, query) and the 'url' parameter is described as 'normalize or cite' rather than 'check open'. This makes the tool's actual purpose ambiguous and inconsistent with its name.

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 on when to use this tool versus sibling tools like browser-url-ok, fetch-status, normalize-url, or status-catalog. The description does not mention alternatives or specific conditions for selection.

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