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

Annotations already declare readOnly, idempotent and non-destructive, so the safety profile is covered. The description adds real context beyond that: what is returned (risk band, labels, roles, alerts, counterparties, plain-language story), the cost model ('Free plan'), and the latency tradeoff of live=true. It does not discuss error handling for unsupported chains, which keeps it below a 5.

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 scope and risk categories are front-loaded in the opening clause, followed by a short usage rule and two operational notes (free plan, live=true). The first sentence is dense with enumerated categories, but each element carries selection-relevant information rather than 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 correctly spells out what the response contains: risk band, labels, roles, alerts, counterparties and a narrative. Combined with the chain-coverage caveat and latency note, an agent has enough to invoke it correctly; only failure/edge-case behavior for unsupported chains is absent.

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 only 33%, so the description must carry meaning — and it partly does, by explaining that chain determines analysis depth and that live=true triggers slower live on-chain screening. The address parameter and the default chain value remain undocumented in the description, leaving a gap against the low schema coverage.

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 and resource ('Wallet and smart-contract risk screening (KYT / AML)') and enumerates the risk categories covered — sanctions, exploits, phishing, drainers, mixers, malicious contracts, first-hop exposure. An agent can tell this apart from screen_entity or screen_transfer because the scope is explicitly an address rather than an entity or a transaction.

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 provides a clear when-to-use rule: 'Use before onboarding, paying or interacting with an address.' It also flags a coverage caveat that functions as a usage constraint — full analysis on EVM chains, sanctions-list-only on Bitcoin, Tron, Solana, Litecoin and Monero. It stops short of naming an alternative sibling for cases outside that scope, so it is clear context without explicit exclusions.

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