Cheapest pre-send address check (lite, $0.01, never "safe")

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

Annotations are minimal (readOnlyHint=false, openWorldHint=true, idempotentHint=false) and the description carries the real behavioral load: it discloses the $0.01 x402 payment on Base, the funding wallet (VERDIX_PRIVATE_KEY), the up-front refusal when above VERDIX_MAX_PRICE_USD, and that a 503 is not charged. It also warns that the tool NEVER returns 'safe', preventing a dangerous misinterpretation of 'no_known_risk'.

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?

Front-loads the cost and the core use case, then the field/verdict semantics, then the escalation path and payment details — a sensible ordering. It is dense and slightly overlong for a one-parameter tool, but nearly every sentence carries decision-relevant information.

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 enumerates the return fields (verdict, risk_score, reasons, checked, limited_checks, checks_performed, not_checked, full_check, as_of), defines each verdict, and covers cost and failure behavior. An agent has everything needed to call this correctly and interpret the result.

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?

Single parameter with 100% schema description coverage, so the baseline is 3. The description adds only marginal value ('EVM address on Base', recipient/contract/counterparty), largely restating what the schema description already says.

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?

States a specific verb and resource (screen an EVM address on Base), names its scope limits (skips address age and caution-only contract checks), and differentiates itself from the sibling check_address_risk_quick. An agent can pick this tool over the other five risk tools without opening a 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?

Gives an explicit when (before sending USDC to an unknown or new recipient), a when-to-escalate (need a 'safe' verdict before a large/irreversible transfer → use check_address_risk_quick), and decision rules for the outcomes ('danger' = do not send, 'caution' = confirm with the user). Very little is left to inference.

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