Which days and times am I free? Reads your calendar feeds and answers with the slots you can offer.
To add when-free to Claude, run the install command below or copy the ready-made config for Claude Code, Claude Desktop, Cursor and VS Code further down. Restart your client after adding it and its tools show up in your next conversation. It needs 2 environment variables, listed below.
Install
uvx when-free@0.4.1Environment variables
WHENFREE_CALENDARSSet in your MCP configWHENFREE_TZSet in your MCP configInstall with your client
claude mcp add when-free --env WHENFREE_CALENDARS=<YOUR_WHENFREE_CALENDARS> --env WHENFREE_TZ=<YOUR_WHENFREE_TZ> -- uvx when-free@0.4.1
Run this in a terminal to add the server to Claude Code.
What this does
when-free exposes a set of tools to Claude over the Model Context Protocol. After you add it to claude_desktop_config.json (snippet above) and restart Claude Desktop, those tools become callable inside any conversation.
Requirements
This server needs the following environment variables to be set before it can run:
WHENFREE_CALENDARS WHENFREE_TZ
Set these via the env object in your MCP config (see claude_desktop_config.json snippet above).
Frequently asked questions
How do I install when-free?
Run the Claude Code command in the install section to add when-free to Claude Code, or copy the ready-made config for your client from the install section on this page. Restart your client afterwards and the tools appear in your next conversation.
Which clients work with when-free?
This page carries setup and config for Claude Code, Claude Desktop, Cursor and VS Code. Any other MCP client that accepts a standard server config can connect to when-free as well.
Does when-free need an API key?
Yes. Before it can run, set these environment variables: WHENFREE_CALENDARS, WHENFREE_TZ. They go in the env block of your MCP config.
Imported from the Official MCP Registry. The details above come from the registry entry; the maker can claim this listing to correct them, add docs, and see its traffic.
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