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

No annotations are provided, so the description carries the full burden. It fails to disclose that the tool makes an external network request (HEAD to a URL), which could have side effects like hitting third-party servers, consuming bandwidth, or being blocked. It also does not specify what 'status' means (e.g., HTTP status code, or something else).

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 extremely brief (one sentence), but it omits critical details such as what 'status' refers to, how the URL is specified, and what the return format is. While brevity is good, the lack of essential information makes it ineffective. There is no structure beyond a simple sentence, so it does not convey a clear mental model.

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, and the description does not explain the return value beyond 'status only,' leaving the exact response format ambiguous. It also fails to contextualize the tool among its many sibling tools, making it impossible for an agent to determine when this tool is the right choice without additional probing.

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 schema descriptions for the parameters are entirely generic and do not align with the stated purpose of checking a URL. For example, 'ref' is described as 'Git ref name; discarded after the shape check' and 'city' as 'City name for a public weather hint; discarded after the call' – none of these relate to a URL. A real URL parameter is absent, so the descriptions add no meaningful guidance and actively contradict the tool's described purpose.

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 the purpose is muddied by the presence of nine parameters that are completely unrelated to URLs (e.g., 'ref', 'city', 'feed', 'zone', 'query'). This suggests the description may be mismatched with the actual tool parameters, so the intended purpose is not clearly conveyed.

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 gives no indication of when to use this tool versus alternatives like browser-url-ok, playwright-url-ok, web-fetch, or normalize-url. It does not mention any prerequisites, limitations, or context in which it should be chosen over sibling tools.

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