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

The description adds substantial behavioral detail beyond annotations: limited free result plus paid upgrade links, two payment paths (x402 via Apify and Bearer token for TidyTools credits), and precise free-tier rate limits (3/IP/day, 50 shared pool, 100 global). These are exactly the operational constraints an agent needs to avoid failed or over-limit calls.

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 front-loaded with the core purpose and return behavior, then layers in payment/auth details, scope boundaries, and rate limits. Every sentence carries operational value, though the payment-method sentence is dense and could be slightly tighter.

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?

Given one simple parameter, an output schema absence, and read-only/open-world annotations, the description covers the important gaps: what is returned (limited free result + paid links), auth requirements, and rate limits. It could be more specific about what 'contact details' includes (emails, phones, social profiles), but it is otherwise complete.

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% for the single 'url' parameter, so the schema already defines it as 'One public HTTP(S) URL.' The description repeats the single-URL constraint ('one website', 'Use for one url') but adds no new format or semantic detail beyond what the schema provides. Baseline 3 is appropriate.

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 clearly states a specific verb and resource: 'Finds public contact details on one website.' It also bounds the scope to a single URL. It does not explicitly distinguish itself from sibling tools like ai_extract or company_enrich, but the one-URL constraint provides some differentiation.

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?

It gives explicit usage context: 'Use for one url. Not for batch work or unrestricted monitoring.' This tells the agent when not to use it. Alternatives are not named, but the exclusion is clear enough for an agent to route correctly.

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