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

With no annotations, the description carries the behavioral disclosure burden. It contributes one meaningful trait: "Page content is not stored," and the parameter schema adds "discarded after the check" for JSON. However, it does not disclose network side effects, auth requirements, rate limits, or whether the operation is purely read-only beyond the storage note.

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 two short sentences with no wasted words; the primary action is front-loaded and the privacy note earns its place. It loses a point because the exceptional brevity comes at the cost of clarifying the heterogeneous parameter set.

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?

With 4 parameters, no output schema, and a description covering only the URL behavior, the tool is under-specified. The description never explains what happens when json or zone are supplied, what the return shape is, or how host/scheme/HTTP status are combined. An agent would have to infer too much.

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 on top of the schema. Worse, it does not explain how json and zone relate to the stated URL purpose, leaving a semantic gap that the schema alone cannot resolve.

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 and resource: "Return host, scheme, and HTTP status for a URL." This is a clear operational goal. However, the presence of unrelated-looking parameters (json, zone) and the tool name "citation" not aligning with the stated operation muddies the overall purpose.

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?

No guidance is given for when to use this tool versus alternatives, nor any exclusions or prerequisites. The garbled sibling-tools list suggests other tools exist, but the description never references them or defines selection criteria.

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