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

Without annotations the description carries the full burden, and it discloses the upstream data source (Ministry of the Interior road-name API), the exact shape of returned fields, the payment model ($0.002 USDC via x402 on Base or Solana), and the not-charged-on-400 behavior. Missing only things like rate limits or caching, which keeps it below a 5.

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?

Front-loaded with the trigger, then Input/Output/Data/Example/Price in tight labeled segments; no filler. Slightly list-like and dense, but every sentence carries information an agent needs.

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?

No output schema and no annotations, so the description must explain returns and cost on its own — it does both, plus the error/charging behavior. Only minor omissions (rate limits, Korean-only input expectation) keep it from a 5.

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%, so the baseline is 3, but the description adds value beyond it: a concrete example query ('?q=테헤란로 152') and the 1-5 bound on limit, which the schema does not state (it only gives default 3).

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+resource ('normalize or translate a South Korean address') with concrete scenarios (shipping, checkout, KYC). No sibling tool overlaps, so the purpose is unambiguous.

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?

'Use when an agent must normalize or translate a South Korean address' gives a clear trigger context, reinforced with example workloads. It gives no explicit exclusion or alternative, but no sibling performs address normalization, so there is little to route against.

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