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

Annotations already cover the safety profile (readOnly, idempotent, openWorld, non-destructive), and the description adds operationally important context beyond them: a 60 calls/minute client rate limit, live public-blockchain reads that take several seconds, and the caveat that results change as the wallet transacts. This is exactly the extra context 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?

One dense paragraph that front-loads the operation and its outputs before usage, exclusions, and operational caveats. Every clause carries information, though the long output enumeration makes it a slightly heavy read compared with a tighter split into purpose/usage sentences.

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?

For a one-parameter read tool with full schema coverage, annotations covering safety, and an output schema handling return values, the description covers purpose, routing, latency, rate limits, and data volatility. Nothing an agent needs in order to call it 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 coverage is 100% and the single parameter is fully documented with its regex pattern, so the baseline is 3. The description adds real meaning by constraining the address to an EVM 0x wallet and by naming the sibling to use for non-EVM chains, which the schema pattern alone only implies.

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+resource ('Run a Know-Your-Agent check on an AI agent's EVM wallet') and enumerates the exact outputs: registry lookup, sanctions screening, on-chain behaviour, risk score bands, and a signed VC plus Merkle proof. It explicitly distinguishes itself from the sibling screen_wallet, so an agent can route correctly without opening either schema.

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 gives an explicit trigger ('before paying, hiring or accepting payment from an autonomous agent') and an explicit exclusion with an alternative ('for an address on another chain, or a list-only check, use screen_wallet'). Both the when and the when-not are stated.

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