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

Beyond the annotations (which only declare read-only/idempotent/non-destructive), the description discloses matching semantics (case-insensitive substring, exact vs partial labelling, partials needing human review), list freshness via lists_as_of, and the payment model ($0.002 USDC via x402, PaymentRequired on unpaid calls, no charge for failures). This is substantive behavioral context the agent could not infer from structured fields.

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 dense paragraph, but it is front-loaded with purpose and list coverage before the routing and pricing details. It is longer than typical, yet nearly every clause carries information an agent needs; only the pricing sentence could arguably be trimmed for brevity.

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 full schema coverage, an output schema covering return values, and annotations covering the safety profile, the description fills the remaining gaps: scope of lists, alias handling, match labelling, freshness signalling, and cost. Nothing needed to call or interpret the tool correctly is missing.

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 all three parameters are fully documented in the schema, so the baseline is 3. The description adds no parameter-level syntax or defaults of its own; its useful detail (aliases, matching behaviour) is behavioral rather than parameter-specific.

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 names a specific verb (screen) and resource (a person/organisation name, including aliases) and enumerates the exact list groups covered, from sanctions and PEPs to OFAC-listed vessels. It is immediately distinguishable from siblings like run_due_diligence and screen_wallet.

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 states its own use case ('a quick list check of a name') and explicitly routes the agent elsewhere: run_due_diligence for a scored profile, search_mauritius_registry for Mauritius licences/offshore/local PEPs, and screen_wallet for blockchain addresses. When-to-use and alternatives are both explicit.

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