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

With no annotations, the description carries the full burden. It usefully discloses the return fields and the cost model ($0.005 per call, USDC on Base), but says nothing about year-range validation, error behavior for invalid or future Jalali years, or whether the list includes unofficial/observed holidays.

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?

Three short sentences, front-loaded with the core purpose, and the cost note is a legitimate practical detail. 'Returns the holiday list' is mildly redundant with the opening sentence.

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?

No output schema exists, so the description must describe the response; it does so minimally (Gregorian date and name per holiday). It omits the overall response shape, ordering, and any limits on which Jalali years are supported.

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 0%, so the description must compensate for the undocumented 'year' parameter. It does add the key semantic that the year is Jalali (Solar Hijri) rather than Gregorian, but gives no format hint (e.g. 1403 as a plain number) or range limits.

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 (return official Iranian public holidays) scoped to a Jalali year, and specifies the returned fields (Gregorian date and name). It does not differentiate itself from the sibling fa_iranHolidayCheck, and the phrase 'flag non-working days' actually blurs the boundary with that checker tool.

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?

Offers two concrete use cases (planning delivery/support schedules, flagging non-working days), which is implied rather than explicit guidance. It never says when NOT to use it or names the obvious alternative, fa_iranHolidayCheck, so an agent could pick this whole-year list tool for a single-date test.

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