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

The description mentions that the body is discarded, but it does not explain what happens with the other schema parameters, whether the request has side effects, or what the response format is. The unrelated parameter descriptions make actual behavior even more opaque.

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 short, but the schema is bloated with nine optional parameters that appear to belong to other sibling tools, making the tool definition not appropriately sized for its stated purpose.

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, no required parameters, no examples, and no explanation of which parameters actually matter. For a tool that appears to make network requests, important context like error behavior and return shape is 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?

Although every parameter has a description, most descriptions are irrelevant to fetching a web URL: e.g., 'ref' is 'Git ref name; discarded after the shape check' and 'zone' is 'IANA timezone name'. No parameter is required, and the relationship between these fields and the stated tool purpose is unexplained.

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 concrete action and resource ('HTTP status and content type for a public URL'), but the schema includes nine unrelated optional parameters such as 'Git ref name' and 'City name for a public weather hint', which muddles what the tool is actually for.

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 guidance on when to use this tool versus the many sibling tools like fetch-status, normalize-url, or validate-json, and no conditions or non-goals are provided.

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