getUsMarketCalendar

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

Adds useful details beyond annotations: nullable sessions, all null on holidays, three business days, times in KST, and rate limit group. No contradictions.

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?

Concise, front-loaded purpose, and every sentence adds value. Could be slightly more structured but is efficient.

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?

Explains output structure (4 sessions, 3 days, nullable) and rate limits, compensating for no output schema. Adequate for a simple tool.

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 covers 100% of the parameter, so baseline is 3. Description does not add much beyond the schema's description of the date parameter but provides response context.

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 it queries US market hours and returns three business days of session info, effectively distinguishing from the sibling getKrMarketCalendar by name and context.

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?

No explicit guidance on when to use this tool over alternatives like getKrMarketCalendar; it only implicitly indicates US market focus.

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