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

No annotations are provided, so the description carries the full burden. It does disclose the payment model ($0.005 per call, USDC on Base), which is genuinely useful behavioral context, but it omits error behavior and what is returned when the date is not a holiday, which an agent needs for a check 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?

A single tight sentence with the core purpose front-loaded and the cost note appended. No waste, though the pricing could arguably live in metadata rather than the description.

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 three-param check tool with no annotations and no output schema, the description covers purpose, return value, and cost, but leaves the Jalali input format and the non-holiday result undefined.

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% and none of the three params (year, month, day) are described. The phrase 'Jalali date' does add real meaning – the year is a Jalali year (~1300-1400), not Gregorian – but no format, range, or validation rules are given.

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 ('Check') and resource ('Jalali date is an Iranian public holiday') plus the return value ('its name'). The singular/plural naming lets an agent infer it differs from sibling fa_iranHolidays, but the description never explicitly contrasts them.

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 when-to-use guidance, no prerequisites, and no alternative named. The agent must infer from the name that fa_iranHolidays returns the full list while this checks one date.

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