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

With no annotations, the description carries the full burden. It discloses the key behavioral guarantee ('never a silent all-clear'), the payment flow (call without x_payment to get terms, then with x_payment to get data), and the live nature of the SDN list. It does not cover error cases or rate limits, but the essential behaviors are transparent.

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 is appropriately sized at three sentences. The payment flow is described in a dense, run-on sentence but every clause carries essential information. Slightly more structure would improve readability, but it is not verbose.

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 core function, return behavior, and the paid payment workflow, which are the major contextual elements. There is no output schema, so the explicit mention of the verdict and evidence is valuable. It lacks details on invalid addresses or network failures, but the description is sufficiently complete for a screening tool with this complexity.

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%, so the baseline is 3. The description's mention of 'segmented by chain' and the payment flow adds some context, but the schema already fully documents each parameter's meaning. The description does not add significant semantic value beyond the schema.

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 opens with a specific verb and resource: 'Screen a crypto address against the full live OFAC SDN list.' It also mentions the return of a verdict with matching SDN entries as evidence, clearly distinguishing it from sibling tools like gas_price or token_safety.

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 context on the two-step payment process and explicitly names the 'pricing' tool as a free alternative for price discovery. However, it does not explicitly contrast with sibling screening tools (e.g., token_safety, nft_scam_check) or state when not to use this tool.

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