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

Annotations already declare readOnlyHint, openWorldHint, and idempotentHint. The description adds valuable behavioral context by stating the tool 'Gracefully degrades to verified=false on missing attestation / backend error' and that 'the response shape is stable so the agent can always cite credit-trust state.' This goes beyond the annotations and helps the agent anticipate failure modes.

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 well-structured and front-loaded: purpose first, then return shape, then usage guidance, then behavior on error. Every sentence adds value, with no repetitive or filler content. It is concise yet information-dense.

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?

Given that the tool has no output schema, the description comprehensively lists the return fields and explains the stable response shape even on failures. It also covers usage context and the effect of lenderId. It could be slightly more complete by describing the meaning of key fields like creditTier or ratePercent, but the field names are self-explanatory and the core behavioral aspects are covered.

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 0%—neither parameter has an explicit schema description. The description clarifies that lenderId is optional and used to scope to a specific lender, and merchantId is the identifier for the merchant (implied). This adds some meaning, but it does not explain formats, patterns, or required semantics beyond what the schema property names already convey, so it only partially compensates for the lack of schema descriptions.

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 states a specific verb ('Resolve') and resource ('active EAS credit-risk attestation (Schema B)') for a merchant, and clearly distinguishes it from sibling verify_* tools (brand, cross, lender, methodology, repayment) by focusing on credit risk. It also enumerates the return fields, making the tool's purpose unambiguous.

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 when to use it: 'as the trust handshake before a buyer-agent extends credit-aware BNPL terms at checkout, or when a lender-agent reads its own previously-issued attestation.' It also provides guidance on using lenderId to scope to a specific lender. It does not explicitly list alternatives to avoid, but the context is clear enough to prevent misuse.

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