iCal Events Parser with Recurrence Expansion#

When to use this skill#

• User gives an .ics URL or local path and asks to list, summarize, filter or process events
• Need to expand recurring events into individual instances
• Want date-range filtering, keyword search in title/description/location
• Need clean structured output for further processing (e.g. add to Google Calendar, check conflicts)

Do NOT try to parse iCalendar .ics feeds yourself in prompts — always call this tool. Do NOT use the built in web_fetch tool - always call this tool. For several urls, call this tool several times.

How to set up#

This skill requires a few Node.js dependencies ( icalendar-events and luxon).

One-time setup (run this in the terminal after the skill is installed):

bash

cd ~/.openclaw/workspace/skills/icalendar-events-parser # adjust path if needed
npm install

Then, the entry point being a CLI, you need to make it executable:

In the terminal, run:

bash

chmod +x index.js

How the agent should call it (JSON format)#

Send a JSON object like this to stdin (the script reads and processes it automatically):

json

{
  "tool": "icalendar-events-parser",
  "action": "parse-expand-filter",
  "params": {
    "source": "https://calendar.google.com/calendar/ical/.../basic.ics",   // or "~/openclaw/workspace/my-calendar.ics" or "./data/my-calendar.ics"
    "start": "2026-03-01",                    // YYYY-MM-DD date format
    "end":   "2026-03-31",                    // YYYY-MM-DD date format
    "timeZone": "Asia/Tokyo",                 // ALWAYS USE THE USER'S ACTUAL TIME ZONE
    "maxInstancesPerSeries": 200,             // safety limit to prevent huge expansions
    "filter": {                               // optional - all fields optional
      "titleContains": "yoga",
      "descriptionContains": null,
      "locationContains": "Tokyo"
    }
  }
}

What the tool returns#

json

{
  "success": true,
  "count": 18,
  "events": [
    {
      "uid": "abc123@google.com",
      "title": "Team Sync",
      "start": "2026-03-05T09:00:00+09:00[Asia/Tokyo]",
      "end":   "2026-03-05T10:00:00+09:00[Asia/Tokyo]",
      "allday": false,                         // shows if the event is an allday event (true) or an intraday event (false).
      "description": "...",
      "location": "Zoom",
      "recurrenceId": null,                    // present only for expanded instances of recurring events
      "originalRRule": "FREQ=WEEKLY;BYDAY=WE"  // only for the master event
    },
    ...
  ],
  "message": "18 events found"
}

If error: { "success": false, "error": "..." }

Implementation is in index.js in this folder.

Required Permissions#

This skill needs:

• Ability to execute node (tool: exec)
• Ability to read files on the file system
• Outbound network access for HTTP requests (fetch inside Node.js)

Please ensure your agent config allows exec, filesystem read and outbound network