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

Annotations declare readOnlyHint=false and idempotentHint=true; the description explains why by disclosing billing rules (84P on first result, free re-query within validity), PARTIAL_SUCCESS unit pricing, and expiry-to-RESULT_EXPIRED behavior. That is real behavioral context (cost, idempotent retry, temporal limits) beyond the annotation flags, and nothing contradicts them.

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 purpose is front-loaded in the first clause, followed by status-handling, billing, and result-path details; every sentence carries operational information. It is dense and the bracketed pricing footnote slightly duplicates the billing sentence, keeping it from a 5.

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 no output schema, the description carries the return contract: check resultAvailable, status, errorCode, and read per-certificate values at result.incomeAmountCert and result.pensionCreditCert. Combined with status enumeration, billing, and expiry handling, an agent has everything needed to call and interpret it.

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% and the schema already specifies the 32-char lowercase hex pattern, so the baseline is 3. The description adds retry semantics — reuse the transactionId from the req_income_cert_bundle response, and the same ID for polling — which is meaningful beyond the schema.

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 (조회) and resource (소득 증빙서류 통합발급 결과) tied to a specific key (req_income_cert_bundle의 transactionId). This clearly distinguishes it from the request-side sibling req_income_cert_bundle, so an agent can pick the right one without reading either schema.

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?

Explicitly gives when-to-use branches: AUTH_WAITING means wait for phone approval, COLLECTING means retry shortly with the same ID, RESULT_EXPIRED means a new application is required. These state the condition and the required next action, including the alternative flow when the result is expired.

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