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

With no annotations, the description carries the full transparency burden and it does disclose the HTTP verb, the public scope, and that it returns no body, only status. This makes the operation's read-only, non-destructive character clear, though it does not cover edge behavior such as redirects or error handling.

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 short, front-loaded sentence contains the essential action, target, and output restriction. Every word earns its place, and there is no filler.

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?

Despite a simple core operation, the tool exposes nine optional parameters and no output schema, yet the description gives no guidance on which parameter to provide or how the 'status only' result is represented. Without more context, an agent may be uncertain how to invoke the tool correctly for non-URL inputs.

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 description coverage is 100obviously, so the schema already documents every parameter. The description adds no additional parameter meaning beyond the most salient 'url' input, which keeps it at the baseline.

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 an unambiguous action verb ('HEAD'), the exact resource ('a public URL'), and the result ('return status only'). This clearly distinguishes it from content-fetching siblings like web-fetch and from browser-based checks like browser-url-ok.

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 operation itself implies a use case: lightweight status-only checking without retrieving content. However, the description does not explicitly say 'use this instead of web-fetch when you need only the HTTP status' or name any alternative, so guidance remains implicit.

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