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

With no annotations, the description carries full responsibility for behavioral disclosure. It transparently states the cost ($1.00 per call, paid in USDC over x402) and scope (31 EVM chains), but does not explicitly state side effects, read-only nature, or limitations. Since it's a screening tool, it likely performs reads only, but that's implicit. The cost and chain scope add value beyond schema, but lacking explicit non-destructive behavior and error cases, I give a 3.

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 three sentences, front-loaded with the core purpose ('Screen a wallet address for sanctions and risk'), then provides scope ('31 EVM chains'), a usage hint ('before you transact'), and cost information. Every sentence adds value with zero waste, making it efficient and easily scannable.

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 the tool has 2 params, no output schema, and moderate complexity, the description sufficiently explains purpose, scope, and cost. It lacks explicit communication about return format or potential errors, but the tool's function is straightforward (screening result). The mention of subscription alternative adds useful context. Minor gap: no comparison to sibling verification tools, but the distinct purpose is clear enough.

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%, with each parameter having a brief description. The tool description adds no additional meaning beyond the schema—it mentions the optional subscription token but not more detail. Per rubric, baseline 3 is appropriate when schema covers all params and description doesn't add significant semantic value beyond that.

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 action 'Screen a wallet address' and the specific resource (wallet). It enumerates concrete capabilities: OFAC SDN sanctions screening, risk scoring, suspicious-activity detection across 31 EVM chains. This strongly differentiates from sibling tools like token verification, making the purpose unambiguous.

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: 'Check a counterparty before you transact with it.' This implies when to use the tool. It also mentions cost implications, which influence usage decisions. However, it does not explicitly contrast with sibling tools (e.g., 'use this instead of token verification for wallet-level checks'), so some exclusions are missing.

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