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

Annotations already cover read-only/idempotent/open-world, so the bar is lower, and the description still adds substantial behavioral context: it declines to assert without a declaration, admits '판정 불가 실토' when 인가일·착공일 data is missing, and flags the 부칙 trap plus the separate 토지거래허가구역 regime. No contradictions. Slightly short of 5 only because it leaves response-shape specifics to '전하라' without describing the output it will actually return.

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 core judgment and the concrete example before the boundary list. The four numbered boundaries and the sibling-routing sentence are dense but each earns its place by preventing a misuse; only mild verbosity keeps 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?

For a deterministic multi-factor legal judgment with no output schema and 100% schema coverage, the description supplies everything an agent needs: inputs to declare, what the tool will and will not judge, the addendum edge case, the separate permit-zone caveat, and where to route adjacent questions. Nothing material is missing.

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 real meaning beyond the schema: it explains that region/project_name auto-join the Seoul stage list, that project_name matches only unique matches, that outside Seoul project_stage must be declared, and that re-declaring the returned stage reproduces the same judgment. That elevates it above the schema-only baseline.

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 (판정) and resource (조합원 지위양도 승계 가능 여부) with the exact legal basis (도시정비법 39조 2항) and the three-way determinant (투기과열지구 × 사업유형 × 단계). The '한남3구역 지금 사도 입주권 나와?' framing makes the concrete decision it renders unmistakable and separates it from sibling policy tools.

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 routes alternatives: realty_policy_rules for statute text, realty_redevelopment for project lists/stage, realty_redevelopment_entitlement when subscription eligibility itself is uncertain, and topic=regulated_area for designation status. It also states scope exclusions (소규모정비사업 not judged, exceptions handed off as forks).

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