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

Annotations cover the safety profile (readOnly, idempotent, non-destructive, openWorld), and the description adds substantial behavioral context beyond that: it admits the three construction-delay exceptions are unjudgeable due to missing 인가일·착공일 data, warns the 재개발 부칙 trap prevents a verdict without a declaration, and instructs the agent to relay exceptions·disclosures from the response. This is unusually candid about limits.

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-loads the core decision in the first sentence, then uses a numbered boundary list that each earn their place as routing rules. It is long, but the length is spent on genuine scope limits and alternatives rather than filler.

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?

Despite no output schema, the description tells the agent what the response contains (exceptions, disclosures) and where the judgment stops, and it enumerates the fallback tools for the questions it refuses. For a read-only judgment tool with 6 params, this is complete enough to call correctly.

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 every parameter is already documented in the schema; baseline is 3. The description adds only marginal parameter meaning (that the judgment multiplies regulated_area × 사업 유형 × 단계 and that Seoul auto-combines stage), which is largely a restatement of the schema's own notes.

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 and resource (조합원 지위양도 가능 여부를 도시정비법 39조 2항으로 결정론 판정한다) and anchors it to a concrete user question ('한남3구역 지금 사도 입주권 나와?'). It is trivially distinguishable from siblings like realty_redevelopment or realty_policy_rules because it says exactly what it decides and what it will not decide.

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?

Provides explicit routing: 조문 원문·예외 목록 → realty_policy_rules(topic=redevelopment_rules), 지정 현황 → regulated_area, 분양자격 불확실 → redevelopment_entitlement, 사업장 목록·단계 → realty_redevelopment. It also states the when-not boundary (소규모정비사업은 별도 법제라 판정하지 않는다). Nothing is left to inference.

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