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

Beyond the annotations (readOnlyHint, openWorldHint, etc.), the description discloses important behavioral traits: screening signals are withheld with 'not_rated' until a coverage floor is met (14 days, 20 payments), measured facts are always returned without intent inference, and the per-call cost ($0.002 USDC via x402 on Base). This adds meaningful transparency about gating and monetization.

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, followed by usage guidance, then gating behavior and cost. Every sentence carries valuable information with no redundancy or 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?

For a single-parameter tool with no output schema, the description adequately covers the return categories (distinct services, spend, contract/EOA, screening signals), explains the 'not_rated' status behavior, and mentions cost. It is complete enough for an agent to invoke and interpret results correctly.

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 parameter description in the schema is clear and complete. The description adds marginal semantic context by referring to the 'paying wallet' and 'paying you,' but does not enrich the parameter's technical meaning beyond the schema.

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 tool's purpose: a know-your-agent profile for a paying wallet, listing specific metrics (distinct services, total spend, contract vs EOA, screening signals). This distinguishes it from sibling tools like wallet_authenticity or endpoint_credit_score by focusing on the payer profile.

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 explicitly says 'Use this to vet a counterparty that is paying you,' providing clear context for when to use it. It does not explicitly exclude alternatives or name sibling tools, but the usage context is strong enough to guide selection.

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