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

With no annotations, the description must carry behavioral disclosure. It does reveal one useful trait: 'Page content is not stored.' But it does not say whether the tool makes an HTTP request, follows redirects, validates the URL, or has any rate limits. This is adequate but incomplete.

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 sentences, front-loaded with the core behavior and output fields. 'Page content is not stored' adds meaningful privacy context without padding. 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?

Given a 9-parameter schema, no output schema, and no annotations, this description is too thin. It does not explain which inputs actually influence the returned host/scheme/status, which are discarded, or whether url is required. An agent needs more context to invoke this tool reliably.

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?

All 9 parameters have schema descriptions, giving 100% schema coverage, so the baseline is 3. The tool description adds no real parameter-level meaning beyond mentioning 'a URL,' and it does not clarify how the unrelated-looking parameters such as city, json, host, and feed relate to the stated purpose.

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 states a specific verb and resource: 'Return host, scheme, and HTTP status for a URL.' This gives an agent a concrete idea of the tool's output. However, it does not differentiate this tool from closely related siblings like fetch-status or normalize-url, so it falls short of 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. 'Page content is not stored' hints at a privacy angle but is not framed as a usage condition or alternative-to-sibling rule. An agent is left to infer when citation is the right choice.

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