Public holidays

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

Annotations already declare read-only, idempotent, non-destructive behavior, so the safety profile is covered. The description adds real behavioral context beyond that: the exclusion of Fridays (the weekly day off) and the shape of each returned record.

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 short sentences with zero filler; the coverage statement comes first and the actionable guidance ('use before suggesting appointment days') is front-loaded where an agent will read it.

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?

With an output schema present, return-value detail is unnecessary, and annotations cover the safety profile. The description supplies the essential scope, exclusion, and usage cue; the only missing niceties are the one-year span limit and any timezone caveat, both of which the schema already handles.

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 100%, including the formatexamples and the one-year maximum span, so the schema carries the parameter burden. The description adds only the phrase 'between two dates', which contributes no syntax or format detail beyond the schema.

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 resource ('Official Iranian public holidays and occasions') and scope ('between two dates'), plus what is returned (Persian occasion name, Hijri date). It is clearly distinguishable from scheduling siblings like pz_free_days or pz_free_slots, though it does not name a 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?

'Use before suggesting appointment days' gives a concrete when-to-use condition, and the note that Fridays are excluded prevents a common misinterpretation. No alternative tool is named for comparison, so it stops short of a 5.

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