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

Annotations cover the safety profile (read-only, open-world, non-destructive), and the description adds genuinely new behavioral context: the result is unpaginated, typically 0-10 entries, says what fields come back, and discloses the $0.005 per-request billing cost. No contradictions. It's only short of details like failure modes or empty-category 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?

The purpose and return shape are front-loaded in a single dense sentence, with the billing note appended last. Every clause carries information, though the sentence is long enough that it reads as packed rather than crisp.

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 compensates by enumerating the return fields (name, domain, TrustScore, review count, location) plus category size and subcategories, and it flags the cost and unpaginated nature. An agent has everything needed to call and interpret it.

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% and the single parameter is fully documented there (slug or full URL with an example). The description restates 'by slug or URL' but adds no syntax or format detail beyond the schema, so baseline 3 applies.

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?

States a precise verb+resource+scope: 'companies most recently added to a Trustpilot category'. The recency qualifier distinguishes it from trustpilot_category_companies (the full listing) without naming it explicitly, and an agent can tell what it fetches from the name alone.

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 'short unpaginated list (often 0-10)' framing implies this is a quick-look tool rather than a bulk listing, which hints at when to prefer it. However, it never explicitly names alternatives like trustpilot_category_companies or trustpilot_category_details, nor states when not to use it.

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