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

The description reveals the request method (HEAD) and that only status is returned, but it omits any details about error handling, rate limits, or side effects. The schema's placeholder-like parameter descriptions (e.g., 'discarded after the shape check') hint at behaviors that are inconsistent with simple status fetching, reducing transparency.

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 is easy to read and front-loaded with the main action. However, it sacrifices necessary detail about parameters and usage, making it too terse for the complex schema.

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 provides no output schema, no example usage, no mention of error handling or edge cases, and leaves the relationship between the nine parameters and the stated purpose entirely unexplained. This incomplete context would leave an agent uncertain how to invoke 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?

Although every parameter has a description, the descriptions are generic and often nonsensical relative to the tool's purpose. For example, 'ref' is described as a 'Git ref name' and 'city' as a 'City name for a public weather hint', but the tool is supposed to check URL status. None of the parameters clearly indicate which one represents the URL to check.

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 specific action ('HEAD a public URL and return status only') but does not distinguish this tool from sibling URL-checking tools like browser-url-ok or web-fetch. The presence of many unrelated parameters in the schema further blurs which resource is actually being operated on.

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 versus alternatives. There is no mention of scenarios where a HEAD request is preferred, nor any examples or conditions that would make this tool the right choice.

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