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

With no annotations, the description carries the burden and does add one meaningful behavioral fact: 'Page content is not stored.' It does not disclose whether a network fetch occurs, error behavior, or how the host/json/zone parameters affect the call, so transparency 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 primary output is front-loaded, and the behavioral note 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 a tool with four optional parameters and no annotations or output schema, the description is too thin. It never explains how host, json, or zone relate to the stated purpose, and it lacks the usage differentiation needed to navigate a 10-tool sibling set.

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 tool description adds no parameter-level meaning beyond mentioning 'URL'; it relies entirely on the schema's per-parameter descriptions.

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 specific action and output: 'Return host, scheme, and HTTP status for a URL.' This is clear and not a tautology. However, it does not distinguish itself from siblings like normalize-url or status-catalog, which likely overlap in function.

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 explicit guidance on when to use citation instead of the sibling tools, nor any exclusions. 'For a URL' is too generic to route an agent, and the 10 sibling tools suggest a real need for differentiation.

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