Holiday Calendar
U.S. federal holidays with observed dates and business-day math. Example from an open-source kit.
MCP server · by modernmustardseed.com
About
Holiday Calendar is an MCP server published by modernmustardseed.com. Marketplaces we read that list it: 1 (Official MCP Registry). The last change we recorded was on 2026-10-12. As of our marketplace pass on 2026-10-14.
What it asks for
- Runs remotely
None of the marketplaces we read publishes its tools or the settings it asks for.
What it declares, asks for and runs, in full
Only install plugins from developers you trust. We list what marketplaces publish and do not test plugins.
Works with
- Claude Code
- Codex
- Cursor
- VS Code
- Copilot CLI
A one-click link opens the client, which asks you to confirm before it adds the server.
From the marketplaces that list it and the MCP transport it declares, as each client documents them. We do not test plugins.
Connect
Commands and configs built only from what its marketplaces declare. We do not run them for you and do not test plugins.
As a remote MCP server
Built from what Official MCP Registry declares.
claude mcp add --transport http holiday-calendar https://starter.modernmustardseed.com/holidays[mcp_servers.holiday-calendar]
url = "https://starter.modernmustardseed.com/holidays"{
"mcpServers": {
"holiday-calendar": {
"url": "https://starter.modernmustardseed.com/holidays"
}
}
}Where it is published
| Marketplace | Status | Version | Figures | Verified | First seen |
|---|---|---|---|---|---|
| Official MCP Registry (Open the registry record) | Listed | 1.0.1 | Forks (GitHub): 0 Stars (GitHub): 0 |
Not marked |
Each figure is the marketplace's own and is never added up across marketplaces. A marketplace that publishes no figure shows none: no number is not zero.
What changed
- Official MCP Registry: repository or package changed
- Official MCP Registry: released version 1.0.1 (was 1.0.0)
- Became a product we track
- Official MCP Registry: appeared
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Data comes from the Official MCP Registry (registry.modelcontextprotocol.io), CC0 1.0. Figures come from our own regular passes over the marketplaces, last read on . We publish no contact details for plugin publishers.