xrpl_sentinel_scan_history

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

With no annotations, the description carries the burden and does disclose the $0.10 USD cost and the 25-record cap, adding useful context. However, it does not explain how the payment_signature parameter facilitates payment or whether this operation mutates any state, trusting the reader to infer the monetary requirement.

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 two concise sentences, front-loading the paid status and core function. Every word adds value, 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?

Despite having no output schema or annotations, the description covers the essential function, the result limit, and the cost, making it adequate for a simple two-parameter tool. It could be more complete by describing the response structure or prerequisites, but the core retrieval task is fully clear.

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% (both parameters have descriptions), so the baseline is 3. The tool description adds the context of 'prior recorded scans' for the address and the cost implication for payment, but it does not provide additional syntax or format details beyond the schema's 'XRPL r-address' and 'x402 payment header'.

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 the exact function: 'Return up to 25 prior recorded scans for an address to read score trajectory over time.' This uses a specific verb, identifies the resource (recorded scans), and clarifies the purpose (score trajectory), distinguishing it from the current-scan sibling xrpl_sentinel_scan.

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 phrase 'prior recorded scans' implies a historical-analytics use case, but the description does not explicitly state when to use this tool versus alternatives. No exclusions or alternative tool mentions are provided, leaving the usage context to be inferred.

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