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

With no annotations, the description carries the full burden; it usefully discloses the commercial model ($0.05 per call via x402/USDC), which an agent must know before invoking. However, it omits that the operation is read-only, result volume/pagination behavior, and error or empty-result handling.

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?

A single front-loaded sentence gives purpose, scope, and the pricing caveat with zero redundant wording. Nothing needs trimming and the most decision-relevant facts come first.

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?

For a simple three-parameter read tool with a fully documented schema and no output schema, the description covers purpose, scope, and cost adequately. Minor gaps remain around result shape/pagination and explicit sibling routing, but nothing essential to invoking it correctly is absent.

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 from/to/authority semantics (formats, 92-day cap, enum values) are already fully documented in the schema. The description only echoes the concepts of date range and authority without adding constraints or format detail, so baseline 3 applies.

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?

States a specific verb (search) and resource (Japanese authority updates from FSA/BOJ/MOF) scoped to publication date range and authority. It implicitly distinguishes itself from jp_authorities_latest and jp_authorities_since by requiring a date range, but never names or contrasts those siblings explicitly.

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 date-range-plus-authority framing implies when the tool applies (historical/range queries), but there is no explicit when-to-use versus alternatives guidance, and no mention of when to prefer jp_authorities_latest or jp_authorities_since. Usage must be inferred from the parameter set.

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