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

With no annotations, the description carries the behavioral disclosure burden. It adds a meaningful guarantee: page content is not stored. However, it does not mention potential network-fetch side effects, how non-URL parameters are handled, or any auth/rate-limit expectations, so disclosure is only partial.

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 with no filler. The first sentence states the output precisely, and the second adds a useful privacy-relevant trait. 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?

For the stated URL use case, the description plus the 'url' parameter schema is enough to invoke the tool, and the return fields are specified despite the lack of an output schema. However, with nine optional parameters and no annotation context, the description does not clarify whether the non-URL inputs are relevant or should be avoided, leaving the tool less complete than it could be.

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 schema already documents every parameter. The description adds no parameter-specific meaning beyond the word 'URL', which maps to the 'url' parameter. Baseline 3 applies because the schema does the heavy lifting.

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 concrete result ('host, scheme, and HTTP status') and a clear resource ('a URL'), so an agent can tell what the tool primarily does. It does not explicitly distinguish itself from siblings such as fetch-status or normalize-url, which keeps it from 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?

There is no guidance about when to use this tool versus alternatives, and no exclusions are stated. The phrase 'Page content is not stored' weakly implies a privacy-preserving citation use case, but it does not direct the agent toward or away from sibling tools.

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