Holiday Calendar
Server Details
U.S. federal holidays with observed dates and business-day math. Example from an open-source kit.
- Status
- Healthy
- Last Tested
- Transport
- Streamable HTTP · MCP 2025-11-25
- URL
- Repository
- ModernMustardSeed/small-business-mcp-starter
- GitHub Stars
- 0
TDQS
Score is being calculated.
Available Tools
5 toolsadd_business_daysAdd business daysRead-onlyIdempotentInspect
Move a number of U.S. business days forward or backward from a date, skipping weekends and observed federal holidays, for due dates, delivery windows and notice periods. The start date is not counted: 1 business day after a Friday is the next Monday, or Tuesday when that Monday is a holiday. Returns the resulting date and every holiday it skipped. Up to 1,000 business days either way.
| Name | Required | Description | Default |
|---|---|---|---|
| start_date | Yes | The date to count from. It is not counted itself, written YYYY-MM-DD (for example 2026-11-26). Covers 2021 through 2100. | |
| business_days | Yes | Business days to move, -1000 to 1000. Negative counts backward. 0 returns the start date if it is a business day, otherwise the next one. |
check_business_dayCheck a business dayRead-onlyIdempotentInspect
Check whether a date is a U.S. business day (a weekday that is not an observed federal holiday). Returns the weekday, the holiday observed that day if any, and the business days just before and just after it.
| Name | Required | Description | Default |
|---|---|---|---|
| date | Yes | The date to check, written YYYY-MM-DD (for example 2026-11-26). Covers 2021 through 2100. |
count_business_daysCount business daysRead-onlyIdempotentInspect
Count the U.S. business days between two dates, both dates included, leaving out weekends and observed federal holidays. Returns the business day count, the weekend days, and each holiday that fell in the span. Spans up to 3,660 calendar days.
| Name | Required | Description | Default |
|---|---|---|---|
| end_date | Yes | Last date of the span, counted if it is a business day, written YYYY-MM-DD (for example 2026-11-26). Covers 2021 through 2100. | |
| start_date | Yes | First date of the span, counted if it is a business day, written YYYY-MM-DD (for example 2026-11-26). Covers 2021 through 2100. |
list_federal_holidaysList federal holidaysRead-onlyIdempotentInspect
List the eleven U.S. federal holidays for one calendar year (2021 through 2100): each holiday's name, its actual date and weekday, the date it is observed when it falls on a weekend (Saturday moves to the Friday before, Sunday to the Monday after), and the rule that sets it, from 5 U.S.C. 6103. Use it to answer which days federal offices close in a year.
| Name | Required | Description | Default |
|---|---|---|---|
| year | Yes | Calendar year, 2021 through 2100. |
next_federal_holidaysFind the next federal holidaysRead-onlyIdempotentInspect
Find the next one to eleven U.S. federal holidays observed on or after a date, with each one's observed date and how many calendar days away it is. Without from_date it starts from today's date in America/New_York and says which date it used.
| Name | Required | Description | Default |
|---|---|---|---|
| count | No | How many upcoming holidays to return, 1 to 11. Defaults to 1. | |
| from_date | No | Start looking on this date, inclusive, written YYYY-MM-DD (for example 2026-11-26). Covers 2021 through 2100. |
Tool Schema Changelog
Recent tool additions, removals, and schema changes observed during successful MCP inspections.
5 tool updates
- First observed
add_business_days - First observed
check_business_day - First observed
count_business_days - First observed
list_federal_holidays - First observed
next_federal_holidays
Publisher details
- Operator
- Modern Mustard Seed · Publisher source
- Operator website
- https://modernmustardseed.com · Publisher source
- Vendor relationship
- First-party
- Trust center
- Not available
- Restrictions
- Not applicable
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