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

With no annotations, the description carries the full burden. It states it provides cryptographic proof of on-chain settlements, includes a live/idle freshness verdict, and notes payer identity privacy. It implies read-only behavior via 'poll this' and describes no side effects. It does not explicitly say 'read-only' but the usage context strongly implies it.

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 reasonably concise, with the core functionality stated in the first sentence. The additional sentences add context about trustworthiness and usage, which is valuable but could be tightened. It front-loads the essential information and avoids excessive verbosity.

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 the tool has no parameters and an output schema exists, the description provides sufficient detail about the return data (tx hash, timestamp, amount, explorer link, lifetime count, freshness verdict). It also explains the purpose and when to use it. No major gaps are present for this simple read-only tool.

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 has zero parameters, so the schema covers 100% of parameter semantics by default. According to the scoring guidelines, a baseline of 4 is appropriate for tools with no parameters.

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 explicitly states the tool returns the last 5 x402 USDC settlements from the AgentPay facilitator on Base L2, with specific fields (tx hash, timestamp, amount, explorer link), plus lifetime count and freshness verdict. This clearly defines the resource and the specific data, distinguishing it from broader settlement tools like get_settlement_pulse.

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 provides a concrete use case: 'Agents can poll this before paying to confirm the rail is live.' This gives clear guidance on when to use the tool. It does not explicitly mention alternatives or exclusions, but the context is sufficient for an agent to decide when it is appropriate.

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