Skip to content
Agentmart
Submit a tool

Holiday Calendar

Holiday Calendar MCP server by modernmustardseed.com

Connector by modernmustardseed.com · Domain verified by the MCP Registry

IndexedMITRemote (HTTP)
Write a review

Install

Works with Claude Code, VS Code, Cursor, Windsurf. Read the repository before you give any tool access to your data.

npx agentmarket install connector/modernmustardseed-com-holiday-calendar

Asks which of your tools to add it to (Claude Code, Codex, Cursor, VS Code, Windsurf, Gemini CLI, Claude Desktop) and shows the change first. See https://agentmart.dev/cli.

Remote endpoint

  • https://starter.modernmustardseed.com/holidays Remote (HTTP)

Get the weekly diff

The weekly diff: one email a week with new agent tools, notable updates and grade changes, plus security alerts for tools you follow. Double opt-in, one-click unsubscribe.

We use your email only for this newsletter. Privacy

About

U.S. federal holidays with observed dates and business-day math. Example from an open-source kit.

Reviews

Write a review

No reviews yet. Installed it? Reviews come from verified installers only. How reviews work

Permissions

What this server can do and what it asks for, from its tool list and install config. Checked Oct 25, 2026.

Tools
5 read · 0 write · 0 deleteRead-only
Secrets
None asked for
Install scripts
Nothing to install (hosted)
Runs as
Hosted (remote endpoint)

Tools by what they do 5

From the running server's own tool list (tools/list) on Oct 25, 2026.

Read 5 · Look things up without changing anything.

  • add_business_days
  • check_business_day
  • count_business_days
  • list_federal_holidays
  • next_federal_holidays

Network hosts it talks to 1

  • starter.modernmustardseed.com · found in remote endpoint, install command

Tools (5)

As the server listed them on Oct 25, 2026. Descriptions are the server’s own words; hidden characters are shown as [U+…].

  • add_business_daysAdd business daysread-only

    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.

  • check_business_dayCheck a business dayread-only

    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.

  • count_business_daysCount business daysread-only

    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.

  • list_federal_holidaysList federal holidaysread-only

    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.

  • next_federal_holidaysFind the next federal holidaysread-only

    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.

Signals

Stars
0
Forks
0
Open issues
0
Last commit
Oct 12, 2026 (17 days ago)
Last release
Oct 12, 2026 (17 days ago)

From GitHub (fetched Oct 24, 2026).

Details

Registry name
com.modernmustardseed/holiday-calendar
Version
1.0.1
Auth
Auth not stated
License
MIT
Repository
github.com/ModernMustardSeed/small-business-mcp-starter
Website
starter.modernmustardseed.com/docs/holidays
First seen
Oct 24, 2026
Last checked
Oct 24, 2026
Source
Official MCP Registrygithub-graphql

More from modernmustardseed.com

Cite this page

Holiday Calendar MCP server. Agent Mart. https://agentmart.dev/connectors/modernmustardseed-com-holiday-calendar (last updated 2026-10-24)