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

With no annotations, the description carries the behavioral burden and discloses important facts: the call is free (no credits consumed) and requires proof of npub ownership to prevent scraping. It does not mention failure modes or side effects, but the read-oriented 'Returns...' wording plus the auth disclosure cover the main risks.

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?

Four short sentences with no filler; purpose and return contents are front-loaded, and the scope distinction, cost, and auth requirement are stated in separate compact sentences. Every sentence earns its place.

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 description is largely complete for selection and invocation: it names what is returned, clarifies account scope, states cost, and flags the auth prerequisite, with output schema covering return structure. It would be more complete if it pointed to the infographic sibling or any pertinent exclusions, but an agent can act on this definition.

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 value by explaining why dpop_token is required (proof of ownership to prevent scrapes) and by clarifying that 'days' maps to recent daily usage logs. The schema already handles technical token construction details.

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?

Clearly identifies the resource (patron's account statement) and the returned content (purchase history, credit tranches, usage breakdown, daily logs). It also distinguishes this from the operator's Authority tax balance, but it does not explicitly differentiate the near-namesake sibling roastify_account_statement_infographic.

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 clear context for when to use this tool: when a patron's spending-account statement is needed, and explicitly says it is not the Authority tax balance. It does not name alternative sibling tools or state when to prefer a different statement format, so it stops short of a 5.

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