Holidays for ChatGPT

io.github.pipeworx-io/holidays

Holidays MCP — wraps Nager.Date API (free, no auth)

client:ChatGPT transport:streamable-http

Install Holidays in ChatGPT

Settings → Connectors → Advanced → Developer mode

https://gateway.pipeworx.io/holidays/mcp

Custom connectors are a paid-plan feature and take a remote URL only. ChatGPT cannot run a packaged server locally. ChatGPT docs