reference-data

get_public_holidays_worldwide

Read-onlyIdempotent

FREE with any API key, including the free key by email (https://usaref.dev/free-key). Same as get_public_holidays, but for every country across all seven brands, not only North American. Unmetered: never counts against the key's allowance. Pass api_key, or send the key as the X-API-Key header on /mcp.

Input Schema

Name	Required	Description
`api_key`	No	Any valid API key. Optional when the key is sent as the X-API-Key header on /mcp.
`country`	Yes	ISO country code, any covered country
`subdivision`	No	Optional ISO 3166-2 region code (e.g. 'DE-BY'). Returns national + that region's statutory holidays, each tagged national/regional. Omit for the national calendar.

Output Schema

Name	Required	Description
`unit`	No
`error`	No	Present on a free refusal or error; no charge
`notes`	No
`stale`	No
`value`	No
`series`	No
`source`	No
`country`	No
`no_charge`	No
`price_usd`	No
`confidence`	No
`disclaimer`	No
`how_to_pay`	No
`bind_series`	No
`explanation`	No
`label_basis`	No	Inputs and the rule ids that produced the two labels
`subdivision`	No
`x_next_bind`	No
`http_endpoint`	No
`coverage_label`	No	How much of the question is covered: ready = complete; partial = held with a disclosed limitation or default; gap = no number served. Rules at /label-rules
`effective_from`	No
`last_confirmed`	No
`confidence_label`	No	Evidence verdict derived from source type, verification age and the stale flag (answers: the weakest series read). Rules at /label-rules
`payment_required`	No	true when the call needs payment; how_to_pay explains x402 or card
`available_subdivisions`	No

Schema Changelog

Changes observed during successful MCP inspections.

Changed4 schema fields changedOct 17, 2026
- removedOutput schema / properties / label_basis / properties / source_type / anyOf
```
Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]
```
- addedOutput schema / properties / label_basis / properties / source_type / type
```
Added value: +[
+  "string",
+  "null"
+]
```
- removedOutput schema / properties / label_basis / properties / verification_age_days / anyOf
```
Removed value: -[
-  {
-    "type": "number"
-  },
-  {
-    "type": "null"
-  }
-]
```
- addedOutput schema / properties / label_basis / properties / verification_age_days / type
```
Added value: +[
+  "number",
+  "null"
+]
```
AddedOct 13, 2026

TDQS

A3.8/5.0

Behavior4/5

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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false. The description goes beyond them with billing behavior ('FREE', 'Unmetered: never counts against the key's allowance') and the auth mechanism (api_key param or X-API-Key header on /mcp), which are real operational traits not derivable from annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness3/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Four sentences, each carrying information, but the lead is the pricing/free-key URL rather than the tool's purpose, which is deferred to sentence two. Front-loading the scope statement ahead of the billing note would make scanning faster.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With an output schema present, return values need not be explained, and the description covers the remaining gaps: global vs North American scope, auth paths, and cost. The subdivision option is left entirely to the schema, which is acceptable but leaves a small amount of context on the table.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema already documents api_key, the country enum, and the subdivision semantics (national vs regional tagging). The description only restates the api_key/header alternative and adds nothing about subdivision, so the baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description establishes scope precisely by anchoring to a named sibling: 'Same as get_public_holidays, but for every country across all seven brands, not only North American.' That lets an agent separate it from get_public_holidays without opening either schema, though the core verb+resource ('return public holidays') is inherited from the sibling rather than stated directly.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The 'not only North American' contrast gives clear selection context against get_public_holidays, and the FREE/unmetered note is a decision factor an agent may weigh. There is no explicit when-not-to-use clause (e.g. latency or rate tradeoff for the worldwide variant), so it falls 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.

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