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

With no annotations, the description carries the full burden and does well: it discloses the fee structure (verify/cost/simulate free, settle free, 1% disbursements), fail-closed refusal semantics, and idempotent settle behavior. It stops short of stating that this is a read-only/no-side-effect call, but the 'policy' framing makes that reasonably clear.

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?

Content is front-loaded with '[FREE]' and packed into a few dense sentences. It is efficient, though the cluster of three URLs (manifest, human page, facilitator) is slightly repetitive and could be tightened.

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 zero-parameter info tool with an output schema already present, the description is complete: it says exactly what the tool returns and supplies both machine- and human-readable policy locations, so an agent needs nothing more to call it.

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?

The tool takes zero parameters, so the baseline is 4; there is nothing for the description to document, and it correctly avoids inventing parameter guidance.

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 resource (the AgentPay x402 facilitator's settlement policy) and enumerates its contents: accepted tokens, fee schedule, refusal rules with codes, and failure handling. It is a clear reference/info tool, though it does not explicitly differentiate itself from nearby siblings like settlement_rail_info or facilitator_live_dashboard.

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?

Usage is implied rather than stated: the mention that 'every 402 payment response from gated endpoints names the policy URL' hints at when an agent would consult it, but there is no explicit when-to-use/when-not guidance and no named alternative among the many sibling info tools.

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