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

With no annotations provided, the description carries the behavioral burden. It clearly discloses the key behavior: the response body is discarded, and only HTTP status and content type are returned. It also scopes the operation to public URLs, which meaningfully informs the agent about safety and scope.

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 two short, information-dense sentences with no filler. The most important behavioral qualifier, 'Body discarded', is placed immediately after the primary purpose, making it easy to parse quickly.

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?

This tool has nine optional parameters, no output schema, and no annotation safety net, yet the description does not explain which parameter drives the fetch or what the exact response shape is. The agent is left to infer how url, host, feed, path, and the other parameters relate to the described behavior, making the definition incomplete for confident invocation.

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?

Schema description coverage is 100%, so the baseline is 3 even though the tool description adds no parameter-specific meaning. The description's reference to 'a public URL' aligns with the url parameter, but it does not clarify how it relates to the other eight optional 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 what the tool returns for a public URL: HTTP status and content type, with the body discarded. This is specific enough to separate it from a generic page-fetch tool, though it does not explicitly distinguish it from similar siblings like fetch-status.

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?

The phrase 'Body discarded' implies it should be used when only HTTP status and content type are needed, not when the body content is required. However, it provides no explicit guidance on when to choose this tool over sibling tools such as fetch-status, browser-url-ok, or normalize-url.

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