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

The description discloses one behavioral trait: 'Page content is not stored'. However, it does not disclose that the tool accepts many unrelated inputs (ref, city, feed, json, path, zone, query) that are apparently discarded after validation, which is a significant hidden behavior given the tool's name and stated URL-focused purpose.

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 a single, front-loaded sentence that states the primary action immediately and adds a clarifying constraint. It is appropriately sized with no filler.

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?

Despite the complex 9-parameter schema with seemingly unrelated fields (git refs, weather hints, RSS feeds, JSON validation, file paths, timezones, search queries), the description only covers the URL aspect. It does not explain the tool's broader shape-check/discard behavior or how this fits with its name 'citation', leaving the overall context incomplete.

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 description does not add meaning beyond the schema—it does not explain how the nine parameters relate to the stated URL purpose or clarify the role of parameters like ref, city, or zone, leaving the overall parameter semantics ambiguous.

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') with a clear resource, which is more concrete than a mere tautology. However, it does not explicitly differentiate from closely related sibling tools like web-fetch, fetch-status, or normalize-url, and the 9-parameter schema suggests a much broader multi-purpose behavior that the description does not reflect.

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 versus the many sibling tools (web-fetch, fetch-status, normalize-url, etc.). There is no mention of prerequisites, suitability criteria, or scenarios where alternatives would be preferred.

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