Holidays of a year

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

Annotations already declare readOnly, idempotent, non-destructive, open-world, so the safety profile needs no restating. The description adds a real behavioral rule beyond them — that Fridays appear only when they coincide with an occasion holiday — which prevents an agent from misinterpreting a missing Friday as an error. It stops short of noting total counts or ordering, but the non-obvious filter is disclosed.

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?

Two sentences, no filler. The core scope and returned fields come first, and the Friday caveat plus sibling handoff follow in a compact second block. Every clause carries information an agent would otherwise have to guess.

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, but the description compensates by enumerating the return content (Gregorian and Hijri dates, weekdays). With one optional parameter fully documented, an agent has what it needs; only minor details like ordering or year-range limits are absent.

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% and the year parameter already documents "Jalali year, e.g. 1405. Omit for current." The description restates the Jalali-year framing but adds no format or boundary detail (e.g. supported year range) beyond the schema, so the baseline of 3 applies.

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 names a specific verb and resource ("List all official holidays") and pins down the scope: a Jalali year, with Gregorian and Hijri dates and weekdays. It also explicitly distinguishes itself from the sibling ti_upcoming_holidays, so an agent can route correctly without opening either 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?

It gives a clear when-not plus an alternative: "For 'the next holiday' use ti_upcoming_holidays." The primary use case (enumerating a full year's holidays) is implied by the verb and scope. It lacks guidance on other nearby choices like ti_month or ti_long_weekends, but the key routing decision is covered.

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