섹터 관련 ETF 조회

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

Annotations already declare this a safe read, but the description adds substantial context beyond them: sort order by prior-quarter market cap with null-market-cap ETFs appended, delisted ETFs excluded, only symbol and name returned, and a specific 404 `sector-not-found` failure mode. It even names the rate-limit group.

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 purpose, then uses a tight bullet list where each item carries distinct information (ordering, return shape, exclusion, error). The opening line largely restates the title, which is the only wasted text.

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?

There is no output schema, so the description must explain the return value itself — it does, stating that only symbol and name are provided plus the ordering rule. Combined with the exclusion and error notes, an agent has everything needed to call this 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 0%, so the description must carry parameter meaning, and it does: `marketCountry` is framed as the market filter and `sectorId` is tied to the sector listing with a documented 404 on unknown IDs. The regex pattern on sectorId is left entirely to the schema, which is a minor gap.

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: returns all ETFs classified in the given sector, filtered by marketCountry. It also pins down scope explicitly with '(하위 섹터 미포함)', which separates it from the broader sector tools without the agent needing to open any 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?

Gives clear routing away from this tool for adjacent data needs — prices via `GET /api/v1/prices` and stock basics via `GET /api/v1/stocks` — and notes the sectorId must come from `GET /api/v1/sectors`. It does not explicitly name `toss_get_sector_stocks` as the alternative for constituent stocks, leaving that to inference from the name.

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