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

Annotations already establish the safety profile (readOnlyHint=true, idempotentHint=true, destructiveHint=false), lowering the disclosure burden. The description adds useful context about what is returned, but does not describe runtime behavior such as performance characteristics, error handling, or authorization requirements beyond the schema's ledger restriction note.

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 with no wasted words. Each clause contributes either the core purpose or a concrete output detail.

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 an output schema present, annotations covering safety, and full schema coverage for the single parameter, the description provides sufficient context for an agent to call the tool correctly. It succinctly summarizes the diagnostic value without duplicating structured fields.

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 sole parameter's meaning, owner/name format, and default behavior are already fully documented in the schema. The description adds no parameter-level guidance beyond what the schema provides, making the baseline 3 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 states a specific verb and resource ('Check one ledger's validity') and enumerates the concrete outputs: bean-check errors with file/line, entry counts per directive type, and the latest commit. This distinguishes it from sibling ledger tools that list, create, or mutate ledger data.

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 'in one call' clearly signals the tool's role as a consolidated validation/diagnostic endpoint, which gives an agent enough context to know when to use it. However, it does not explicitly name alternatives or state when not to use it versus tools like listLedgerEntries or getLedgerContext.

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