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

With no annotations, the description carries the behavioral burden and usefully discloses the payment challenge, 1 USDC Base settlement, and Ed25519-signed output. It omits error behavior, permission requirements beyond payment, and idempotency semantics, so transparency is only partial.

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?

Three sentences, front-loaded with the action and the payment workflow, with no obvious filler. It could be slightly tighter, but it is well structured.

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?

The tool has six parameters, a nested provenance object, no annotations, and no output schema. The description covers the payment flow and signed result but does not explain the output structure, API-key bypass, or how it relates to sibling tools, leaving meaningful gaps.

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 100%, so the baseline is 3. The description adds meaning for payment_signature and the unpaid challenge flow, but it does not explain the roles of subject, provenance, api_key, or idempotency_key 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 uses a specific verb and resource: evaluate a proposition and receive a signed Standing determination. It is clear what the tool does, but it does not distinguish itself from the sibling tools whp_standing_evaluation or whp_standing_result.

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 operational sequencing: call without payment to get the x402 challenge, then pass payment_signature to settle. It does not state when to use this tool versus the sibling standing tools, so alternative selection is left implicit.

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