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

With no annotations, the description carries the full burden, and it does disclose material operational facts: 'Auth mode: paid' and exact pricing ($0.005 per call via x402/MPP). However, it says nothing about return format, whether holidays include Gregorian dates, caching, or failure behavior.

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?

The payload is dominated by auto-generated boilerplate — Origin URL, hostname, brand, endpoint, six keyword lines, and duplicated source description — before and around a single functional sentence. The useful summary is present but buried under low-value metadata.

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 one-parameter read tool with no output schema, the description covers purpose, a Jalali-year example, and the paid auth requirement. It still leaves the return shape (holiday names, Gregorian equivalents, whether Nowruz spans multiple days) unaddressed.

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% for the single 'year' parameter, so the description must compensate. It partially does, by framing the value as a 'Jalali year' and the example 'Jalali year 1405' implying the number format (no 1xxx ambiguity resolution beyond that), but the accepted range and boundaries are never stated.

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 summary states a clear verb and resource: 'List the official Iranian public holidays for a Jalali year, including Nowruz and religious occasions.' It is distinguishable from the singular sibling iran_holiday_check (which checks one date), but it never names or routes to that sibling explicitly.

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?

Three 'Use case' lines give context (list holidays for Jalali 1405, check whether Nowruz is a working day, get the yearly calendar), but all three restate the same retrieval scenario rather than differentiating from iran_holiday_check or business_days. No when-not guidance or exclusions are provided.

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