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

Annotations only declare readOnlyHint and openWorldHint; the description adds genuinely new behavior: which upstream lists back the result, refresh cadence (daily), conditional augmentation via a Chainalysis key, failure semantics ('fails and is not charged if the list is unavailable'), and price ($0.001 USDC per call). That covers cost, degradation, and false-negative risk that annotations cannot express.

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?

Three dense sentences, all load-bearing, with the decision trigger stated first and the caveat/cost last. The opening sentence is long and nests a relative clause, which costs a little readability, but there is no filler.

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 no output schema, the description carries return-shape information itself (lists matched, address count per list, fetch timestamp), plus cost, failure mode, and the key limitation that a non-match is not clearance. Nothing an agent needs in order to call this correctly or interpret a result 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 the single required parameter 'address' is already documented as a Solana or EVM (0x…) address in the schema itself. The description adds no format, validation, or casing guidance beyond that, so the baseline 3 applies.

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 first sentence names a specific check (OFAC SDN published crypto addresses) applied to a specific resource class (Solana or EVM address), with the exact upstream source. It is unmistakable next to siblings like token_risk_score, protocol_risk_check, or secrets_detection, which screen different things.

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 phrase 'before an agent sends funds to it' gives an explicit trigger condition, and the 'Informational, not a compliance decision' line sets the boundary on what the result may be used for. It stops short of naming any alternative screen (e.g., token_risk_score) for adjacent questions, so not quite a 5.

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