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

The description mentions that the body is discarded, giving some insight into processing behavior. However, it does not disclose access requirements, rate limits, or side effects. The presence of unrelated parameters (city, feed, zone) without explanation undermines transparency about the tool's actual 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?

The description is a single, concise sentence that directly states the core behavior without unnecessary verbiage. It is appropriately sized for the information it conveys, though it lacks details about the parameters.

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 lacks essential context: it does not explain the role of the nine parameters, the output format, error conditions, or prerequisites. Given the large parameter set and no output schema, this is insufficient for an agent to use the tool 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?

The parameter descriptions are inconsistent with the stated purpose. For instance, 'url' is described as 'HTTPS URL to normalize or cite' rather than to fetch, and parameters like 'city' and 'zone' suggest unrelated functionality. This makes it impossible to understand how to correctly use the parameters.

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 clearly states the tool's function: fetching a public URL and returning HTTP status and content type, with the body discarded. This is specific, not a tautology, and provides useful detail that distinguishes it from simple URL normalization or checking tools.

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 alternatives like fetch-status, browser-url-ok, or normalize-url. The description only states what it does, not the conditions under which it should be selected.

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