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

No annotations are provided, so the description must carry the full behavioral burden. It discloses one useful trait — 'Page content is not stored' — which informs the agent this is a stateless metadata check. But it does not disclose what happens for invalid URLs, whether this is a read-only operation, whether a network call is made, how errors are represented, or what the return format is. For a tool with zero annotations, this is a meaningful gap.

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 and front-loaded with the core output (host, scheme, HTTP status), then a single clarifying sentence about content handling. Every clause earns its place; no filler. It loses one point because the terse phrasing 'Return host, scheme, and HTTP status for a URL' omits any mention of the other clearly supported inputs (json, zone), making the description slightly misleading about what this tool actually accepts.

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 the tool has 4 optional-looking parameters, no required params, no output schema, and no annotations, the description is under-specified. The summary line covers only the URL case while the schema includes json and zone — an agent seeing this description would not know why those params exist, how they affect the result, or what a successful vs failed call looks like. Sibling names like validate-json suggest these params matter, but the description gives no guidance.

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 all four parameters precisely. The description adds the semantic note that page content is not stored, which ties loosely to the 'json' param's 'discarded after the check' phrasing but does not explain how the parameters interrelate. This meets the baseline of 3 but does not exceed it — no additional semantics, format constraints, or intended use of 'host', 'zone', or 'json' are clarified 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 verb ('Return') followed by the resources (host, scheme, HTTP status) and the target (a URL), declaring what the tool computes. However, it doesn't differentiate itself from the many sibling tool-names that strongly overlap in domain (normalize-url, inspect-nodes, validate-json, etc.), so an agent cannot tell this tool's operation apart from closely related alternatives.

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 siblings such as normalize-url, validate-json, or status-catalog. The description implies a use case (citing a URL) but provides no exclusion criteria, no prerequisites (e.g., HTTPS required), and no mention of when the accompanying params like zone or json would be relevant. An agent has to infer the scope entirely.

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