get_us_market_calendar

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

With no annotations, the description carries full responsibility for behavioral transparency. It discloses that the tool returns session-wise information and covers three business days, which is useful. However, it omits details such as timezone, holiday handling, authentication requirements, or exact return format, which are relevant for a market calendar tool.

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 description is two concise, front-loaded sentences. The first sentence states purpose, and the second details session and day coverage. No redundant information or filler words are present.

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 simple tool with one optional parameter and no output schema, the description covers the key points: US market, session types, and 3-day range. It is reasonably complete, though it could mention timezone or holiday behavior to be fully self-contained, but these are not critical for a basic calendar query.

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?

The single parameter 'date' is fully described in the schema with format (YYYY-MM-DD), local US date, and default behavior (today if omitted). The tool description adds no extra parameter semantics beyond this, so the high schema coverage (100%) leads to the baseline score of 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?

The description clearly states the tool's verb ('조회합니다' = queries) and resource ('미국 시장의 장 운영 시간' = US market trading hours). It further specifies the output breakdown by session (day/pre/regular/after) and the 3-business-day coverage, distinguishing it from the sibling 'get_kr_market_calendar'.

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?

The description provides clear context: it is for US market hours, which implies use when US market calendar data is needed. However, it does not explicitly mention alternatives or when not to use it, such as a direct note to use 'get_kr_market_calendar' for Korean market hours, leaving this inference to the tool name and sibling list.

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