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

No annotations are provided, so the description carries the transparency burden. It usefully discloses that the tool uses HEAD and returns status only, but it omits redirect handling, timeout/error behavior, and whether any parameters other than the URL are actually honored.

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?

One sentence, front-loaded with the verb and target, with zero filler. Every word earns its place.

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?

For a tool with nine optional parameters, no output schema, and no annotations, a single sentence is insufficient. It leaves the return format, the relevant parameter, and the relationship to sibling URL/status tools unexplained.

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 coverage is 100%, so the baseline is 3, but the description gives no mapping to the nine optional parameters. The `url` schema description says 'HTTPS URL to normalize or cite', which conflicts with the stated HEAD-status purpose and leaves the agent unsure which field to populate.

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 names a concrete HTTP method (HEAD), a target class ('public URL'), and the exact output ('status only'). This distinguishes it from content-fetching tools like web-fetch and URL-normalizing tools like normalize-url.

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 description implies the obvious trigger — use when you need only the HTTP status of a public URL — but it never states when not to use it or points to siblings such as web-fetch or browser-url-ok. With 28 sibling tools, the lack of explicit routing leaves some overlap unresolved.

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