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

With no annotations, the description carries the disclosure burden. It does reveal one behavior ('Page content is not stored') but does not mention read-only behavior, network activity, error handling, or how the tool handles the nine optional parameters. The mismatch between the single-purpose description and the schema's many unrelated fields creates confusion rather than clarity.

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, no filler, and the first sentence front-loads the core operation. The second sentence adds a useful behavioral disclosure. Every word earn 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, a two-sentence description centered only on URL handling is far from complete. The agent is left without either a high-level understanding of the tool's broader behavior or any indication of the response format.

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 coverage is 100%, so the baseline is 3. The description does add output semantics for the URL parameter (host, scheme, HTTP status) beyond the schema's 'normalize or cite', but it provides no information on how the other eight parameters relate to the tool's behavior.

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 operation: return host, scheme, and HTTP status for a URL. This identifies a concrete resource and action. However, it does not distinguish the tool from close siblings like fetch-status or normalize-url, and it makes no mention of the large set of unrelated parameters in the schema, so it is not 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?

The description gives no guidance on when to use this tool instead of its siblings, no mention of prerequisites, and no exclusion conditions. An agent would not know if this is the right choice among the many URL-handling tools.

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