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

Annotations already mark it read-only and open-world. The description adds useful behavioral context by noting data is 'reconstructed from chain data' and that a $0.01 USDC cost applies, which is not present in annotations. No contradictions with the annotations.

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 a single, front-loaded sentence that conveys the core purpose and a key cost detail with no extraneous words. It is concise and well-structured, earning full marks.

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?

With 7 parameters and no output schema, the description is under-specified for a tool of this complexity. It doesn't mention date range handling, grouping options, direction filtering, or the return structure beyond 'totals + per-service breakdown.' More context is needed for correct invocation in varied scenarios.

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 high at 86%, so the schema already explains most parameters. The description only loosely implies grouping via 'per-service breakdown' and doesn't add meaning to specific parameters like wallet, date range, or direction. Baseline 3 is appropriate.

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 provides x402 spend accounting with totals and per-service breakdown for any Base wallet, clearly identifying the resource and function. However, it doesn't explicitly differentiate from the sibling ledger_report, so it stops short of a 5.

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 gives no guidance on when to use this tool versus alternatives like ledger_report or investigate_wallet. There are no explicit use cases, exclusions, or references to sibling tools, leaving the agent to infer usage from the purpose alone.

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