Apple Calendar

io.github.redpopPublished by GitHub account redpopv0.2.1Updated Nov 3, 2026

Read and create Apple Calendar events on macOS, and find free time across calendars.

VerifiedSTDIODesktop onlyLocation & LifestyleProductivity & Workflow

Overview

AI-generated overview

Local macOS MCP server that lets an assistant read, create, update and delete Apple Calendar events and find free time across calendars.

What you can do
  • List calendars and read events in a date range, with optional text search
  • Create, update and delete events with location, notes, alarms, all-day or timed settings
  • Find free time: returns open gaps rather than busy blocks, with work/personal hours and optional buffers around meetings
  • Handle recurring events as individual occurrences, requiring an explicit choice of one occurrence or all later ones when changing or deleting
When to use it
Useful when you want an assistant to answer scheduling questions on a Mac, such as finding a two-hour focus block this week, proposing slots for a call, or booking and editing events directly in Apple Calendar.
Requirements
macOS 14 (Sonoma) or newer and Node.js 20 or newer; runs locally via npx with no environment variables. On first use, macOS asks to grant the bundled calendar-helper full calendar access, which must be set to Full Access rather than Add Only in System Settings.
Before you install
The assistant can create, update and delete calendar events, including recurring occurrences, so changes affect real data. It requires full calendar access, which is broader than read-only. Calendar data stays local: the project states there is no network code.

Installation

In SourceWeft

  1. Open Apple Calendar in the dashboard and add it to a workspace.
  2. Enable the server for the chats that should use its tools.

Desktop only via STDIO. STDIO servers start a local process, so they need the SourceWeft desktop host.

Other MCP clients

Follow the launch instructions in the repository.

README

apple-calendar-mcp

An MCP server that lets an AI assistant read and create events in Apple Calendar — and work out when you actually have time.

macOS only. It talks to EventKit, Apple's own calendar framework, which has no cross-platform equivalent.

bash
claude mcp add apple-calendar -- npx -y @redpop/apple-calendar-mcp

No Xcode, no Swift toolchain, no repository clone. The signed helper binary ships inside the package.

What it does

Most calendar integrations answer what is on my calendar. This one also answers when am I free:

"Find me two hours for deep work this week, outside meetings""When could I fit a 30-minute call with someone in Berlin?""Book focus time Thursday morning"

find_free_time returns the open gaps, not the busy blocks. It understands that "work" means weekdays during working hours, that "personal" means any day, and that all-day events usually shouldn't count as busy.

It can also keep a buffer around each meeting, because a gap wedged directly between two calls is free on paper and useless in practice.

Alongside that, the usual: list calendars, read events in a range with optional text search, create, update and delete events with location, notes, alarms, all-day or timed. Recurring events come back as individual occurrences, not as the master event — a detail AppleScript-based servers routinely get wrong.

Changing or deleting an occurrence of a recurring event requires saying explicitly whether you mean just that one or every later one too. There is no default for that, because "cancel this Tuesday" and "never again" are not the kind of thing to guess at.

Full parameter reference: docs/tools.md.

Requirements

  • macOS 14 (Sonoma) or newer
  • Node.js 20 or newer

Nothing else. Building from source additionally needs Xcode Command Line Tools, but installing from npm does not.

Setup

1. Add the server to your client.

Claude Code
bash
claude mcp add apple-calendar -- npx -y @redpop/apple-calendar-mcp
Claude Desktop

Quit Claude Desktop first (Cmd+Q) — it rewrites its config on exit, so editing while it runs discards your change. Then add to ~/Library/Application Support/Claude/claude_desktop_config.json:

json
{  "mcpServers": {    "apple-calendar": {      "command": "npx",      "args": ["-y", "@redpop/apple-calendar-mcp"]    }  }}
Cursor, Windsurf, Zed and other MCP clients

Any client that speaks MCP over stdio works. The command is npx, the arguments are -y @redpop/apple-calendar-mcp, and no environment variables are needed.

2. Grant calendar access on first use.

Ask your assistant "what calendars do I have?". A system dialog appears asking to let calendar-helper — not your assistant, the helper itself — access your calendar.

Confirm it, then open System Settings → Privacy & Security → Calendars → calendar-helper → Options… and make sure Full Access is selected, not "Add Only". Read-only access is not enough; the helper checks for full access at startup.

This one dialog is the only manual step, and no package format can take it away. It appears once and survives updates.

Why the dialog says "calendar-helper"

macOS grants calendar permission to the responsible parent process, not to the program actually asking. An AI client that declares no calendar usage in its bundle therefore locks out everything it starts — silently, with no dialog and no entry in System Settings. Several MCP calendar servers work around this by telling you to launch your client from a terminal.

This one doesn't need that. The helper disclaims that inherited responsibility at startup and becomes its own permission identity, so macOS reads the usage description from its bundle and prompts under its own name. One grant then covers every client on the machine.

The full story: docs/architecture.md.

Updating

bash
npx -y @redpop/apple-calendar-mcp@latest

Your calendar grant survives updates: the helper is installed to a fixed path, and macOS binds the grant to that path rather than to the binary's contents.

Uninstalling

Remove the apple-calendar entry from your client's MCP configuration and restart it. Then delete the helper and its permission:

bash
rm -rf ~/Library/Application\ Support/apple-calendar-mcp

The entry under System Settings → Privacy & Security → Calendars stays behind — macOS keeps those even when the binary is gone. Switch it off there if you want it revoked.

Building from source

bash
git clone https://github.com/redpop/apple-calendar-mcp.gitcd apple-calendar-mcpnpm install && npm run build && ./swift/build.sh

Then point your client at dist/index.js with node instead of using npx. Without a Developer ID certificate the helper is signed ad-hoc, and macOS then ties the calendar grant to the exact build — expect a new permission dialog after every rebuild.

Learn more

Privacy

Everything runs locally. Calendar data goes from EventKit to the helper to the MCP server to your client, and nowhere else. There is no network code in this project.

License

MIT — see LICENSE.

Source: README.md at commit 76eab81

Tools

0
SourceWeft has not started this package in its sandbox yet, so its tools are not known.

Version history

1
  1. v0.2.1LatestSep 16, 2026

Score

50% of the applicable checks met

How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.

  • Reached in the last 30 days25 pts

    Keep the endpoint answering the MCP handshake; SourceWeft probes it every 30 days.

  • Auth declared10 pts

    Declare the credential headers in the registry entry, or keep the endpoint answering the probe so its auth can be classified.

  • Tools listed15 pts

    Answer tools/list without a credential, or ship a package that starts in a sandbox without one.

  • DescriptionRequired15 pts
  • Logo10 pts
  • Documentation15 pts
  • License10 pts