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

The description discloses one important behavior: the body is discarded and only the HTTP status is relevant. With no annotations provided, the description carries the full burden, but it does not mention redirects, timeouts, side effects, or whether any request is actually made beyond the status check. It is minimally transparent but leaves key behaviors unspecified.

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?

Two short sentences, front-loaded with the core purpose and followed by the key behavioral detail. There is no filler or redundancy; 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?

The definition is far too sparse for a tool with 10 optional parameters, no required parameters, no output schema, and no annotations. It does not explain what happens when no parameters are provided, what output format the status takes, how the other parameters relate to the operation, or how this tool differs from closely related siblings.

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?

Although the schema provides 100% parameter description coverage, the tool description does not help map the 'public library docs URL' to a specific parameter. The schema's 'url' description says 'HTTPS URL to normalize or cite,' which conflicts with the HTTP-status purpose, and the other nine optional parameters are left unexplained relative to the tool's stated behavior.

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 specific operation—returning an HTTP status for a public library docs URL—and even clarifies that the body is discarded. It is more specific than a generic fetch tool, though it does not explicitly differentiate itself from sibling tools like fetch-status or 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 phrase 'public library docs URL' and 'body discarded' imply that the tool should be used when only an HTTP status is needed and not when the response body is required. However, the description gives no explicit when-not-to-use guidance and does not name alternatives among the many siblings with overlapping URL/status responsibilities.

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