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

With no annotations, the description carries the full disclosure burden. It does add one useful behavioral fact — 'Page content is not stored' — which addresses a real privacy/retention concern. However, it does not disclose the tool's behavior for the json and zone inputs, nor any network-fetch side effects beyond the implication of an HTTP status check.

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 filler and front-loads the primary behavior. It earns points for efficiency, though it trades away completeness of the tool's multi-function scope.

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?

The description plus 100% schema coverage is sufficient for an agent to invoke the URL-citation mode correctly, but the json and zone modes rely entirely on schema text. With no output schema and no usage guidance for a multi-purpose tool, the description leaves meaningful gaps around when and how to use those modes.

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. The description adds no extra meaning about parameter formats, combinations, or constraints, but the baseline of 3 is appropriate since the schema does the heavy lifting.

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 action ('Return host, scheme, and HTTP status for a URL'), which clarifies the otherwise ambiguous tool name 'citation'. However, the input schema accepts json and zone parameters, indicating additional behaviors (JSON validation and timezone checks) that the description completely omits, so the stated purpose is incomplete.

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 on when to use this tool versus the sibling tools (validate-json, timezone, etc.), nor any mention of which parameter combinations are appropriate. The description implies a URL-citation use case but provides no exclusions or alternatives, which is especially problematic since the tool has multiple unrelated parameters and zero required parameters.

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