calendar_holidays

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

No annotations are provided, so the description carries the full behavioral burden. It does explain the include_weekends default and the calendar_overrides scoping ('applies to every use of that calendar while the request is processed and is discarded afterwards'), which is genuinely useful context. But it does not say whether this is a read-only operation, any auth or rate-limit behavior, or error conditions.

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 one-line purpose, then an Args block, then a brief note on summary. Efficient and well structured, though the trailing 'summary = {count, first, last} taken from the engine's response' sentence is low-value since an output schema exists.

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 five-parameter calendar query with an output schema and no annotations, the description covers the purpose, all five parameters with formats and defaults, and the transient nature of overrides. The remaining gap is the absence of any when-to-use routing against the two sibling calendar tools.

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 compensate, and it does: it documents calendar (with example enum values TARGET, UnitedStates), start_date/end_date as inclusive YYYY-MM-DD, include_weekends default False, and calendar_overrides structure with added/removed_holidays semantics including 'weekends are rejected'. Only the nested CalendarOverride contract is partially duplicated from $defs; the core five parameters get real added meaning.

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+resource: listing holidays of a QuantLib calendar between two dates, and even names the underlying endpoint POST /calendar-holidays. An agent can distinguish this from sibling calendar_business_days or calendar_advance without opening 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?

Usage is implied by the resource (holidays between dates) and the endpoint hint, but the description never states when to prefer this over calendar_business_days or calendar_advance, nor prerequisites. Minimum viable guidance only.

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