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

Annotations already declare readOnly, idempotent, non-destructive and open-world, so the safety profile is covered. The description adds that results come from an external LLM provider (Perplexity Sonar) via citation inspection, but omits cost, latency, non-determinism of model output, and API-key failure behavior.

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?

A single sentence that front-loads the mechanism and ends with the outcome. No filler, nothing redundant.

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 no output schema, the description does the necessary work by stating the return value is citation presence plus rank. Minor gaps remain around error cases and whether rank is across all citations or only the target URL's position.

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 all three parameters (url, prompt, perplexityApiKey) are already documented, including the BYOK note. The description restates prompt and URL without adding format, constraints, or matching semantics (e.g., exact vs. subdomain URL matching).

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 concrete verb chain (query Sonar, inspect citations) and a concrete outcome (whether the URL is cited, and at what rank). An agent can tell this is a single-prompt citation check rather than a site-wide audit, though it never names the sibling tools it differs from.

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?

Usage is only implied: the singular 'a prompt' and 'the given URL' suggest one-off testing versus the aggregate siblings (get_visibility_report, compare_competitor_visibility). There is no explicit when-to-use, when-not-to-use, or named alternative.

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