calendar.holidays

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

Being read-only and non-destructive is obvious from 'list'. Description details behavioral traits: includes substitute days, computed movable feasts, and lunar-calendar holidays. No contradictions or missing safety info.

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 sentences front-load the core purpose and include key details without redundancy. Every sentence adds value.

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?

Describes return format ({date, name, type, substitute, rule}) despite no output schema. Covers main functionality comprehensively for its complexity.

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 description adds context beyond parameter descriptions by explaining filtering by type and language localization, and regional subdivisions.

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 clearly states the tool lists official holidays for a country and year, with exact observed dates and substitute days. It covers 200+ countries and regional subdivisions, distinct from sibling calendar.business-days.

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?

The description implies usage for holiday lookup but does not explicitly differentiate from sibling tools like calendar.business-days or provide when-not-to-use guidance.

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