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

With no annotations, the description carries the full burden, but it only discloses that the body is discarded. It does not mention redirects, timeouts, error handling, or whether a network request is actually made, leaving important behavior 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?

The description is two short sentences with no filler, and the core purpose is front-loaded. It is brief, though almost too sparse given the parameter complexity.

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?

With 9 optional parameters, no output schema, and no annotations, this definition does not explain the return format, which parameter is the URL to check, or how it relates to sibling status tools. The agent has too much ambiguity to use it correctly.

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 input schema has 100% property descriptions, those descriptions are generic and disconnected from this tool's purpose, e.g., url is documented as 'to normalize or cite' rather than to fetch status. The description itself gives no clue which of the nine optional parameters should be supplied, so the agent cannot confidently invoke it.

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 clearly identifies the operation as returning HTTP status for a public library docs URL and notes the body is discarded, which is specific and differentiates it from content-fetch tools. It lacks an explicit verb like 'returns' and does not name sibling tools, so it does not reach a 5.

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?

No guidance is given for when to use this tool over related siblings such as fetch-status, browser-url-ok, or web-fetch. The phrase 'public library docs URL' gives some context but no exclusions or alternatives.

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