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

With no annotations, the description carries full burden. It discloses key behavioral traits: payment requirement, x402 protocol, Ed25519-signed results with a freshness timestamp, and that unpaid calls return a payment requirement. It does not describe rate limits or error handling, but covers the critical payment and signature aspects well.

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?

Two sentences with zero wasted words. The first sentence states purpose and key features (OFAC, freshness, signed). The second explains the payment model. Efficient and front-loaded.

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?

The description covers the payment requirement and what happens without payment, but does not describe the output format of a verdict (e.g., a match/mismatch or the structure of the signed result). Since there is no output schema, a brief output description would improve completeness.

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% (both parameters have descriptions). The tool description does not add parameter-specific details beyond the schema; it adds overall context (payment, signature) but not parameter semantics. Baseline is 3.

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 the tool's purpose: 'OFAC SDN sanctions name screen: matches a legal name against the OFAC Specially Designated Nationals list'. It specifies the verb 'screen' and the resource 'legal name against OFAC SDN list', and the mention of payment and signature distinguishes it from siblings like claim_verdict or file_dispute.

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 provides clear usage context: it is a paid tool ($0.001 USDC via x402) with no free tier, and explains that an unpaid call returns the payment requirement. It does not explicitly list when not to use it or compare to alternatives, but the sibling tools are distinct enough that this is not a major gap.

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