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

With no annotations, the description carries the full burden and it does add one useful behavioral fact: 'Page content is not stored.' This helps with privacy expectations. However, it does not disclose other behavioral details, such as whether any input is retained, what happens to the non-URL parameters, or what side effects beyond return values exist.

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. The primary behavior is front-loaded, and the privacy note is a meaningful addition. 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 tool has 9 optional parameters, no output schema, and no annotations, so the description must do more to orient an agent. It explains what is returned but not how to select or prioritize inputs, which parameters are relevant, whether multiple parameters should be provided together, or what happens when they are. An agent would have to rely entirely on the schema to figure out usage.

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?

Schema description coverage is 100%, so the baseline is 3. The description only reinforces that the tool is 'for a URL' but does not clarify the intended relationship among the nine parameters or that most seem to be discarded. It adds little semantic value beyond the schema.

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 specific action ('Return host, scheme, and HTTP status') and a clear target resource ('a URL'), so an agent can tell what the tool fundamentally does. It does not explicitly distinguish this tool from overlapping siblings like fetch-status or normalize-url, so it misses the top tier.

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?

There is no guidance on when to prefer this tool over alternatives such as fetch-status, normalize-url, or browser-url-ok, and no exclusion criteria. Given the large sibling set, an agent would have to guess which tool is appropriate in a given scenario.

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