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

With no annotations, the description carries the full burden of explaining behavior. It mentions HEAD and public URLs, but it does not cover error behavior, redirects, timeouts, or whether only the 'url' parameter is actually used.

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 with no redundant wording. It is well structured and easy to parse.

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 is too minimal given the unusual schema with nine optional parameters and no output schema. It does not explain the return format, which parameters are honored, or how to handle invalid URLs, leaving important context missing.

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 includes nine parameters, but the descriptions are mostly irrelevant or misleading for a status-check tool. For example, 'url' is described as 'HTTPS URL to normalize or cite', and parameters like 'city', 'feed', and 'zone' appear unrelated to fetching HTTP status. There is no guidance about which parameter is required for the core operation.

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 'HEAD a public URL and return status only' clearly states the verb, resource, and output. It unambiguously indicates this is a lightweight HTTP status check.

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 'return status only' gives some sense of when to use the tool, but it does not contrast with sibling tools like browser-url-ok, playwright-url-ok, or web-fetch. There is no explicit guidance on when this tool should be preferred over alternatives.

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