iCalendar parse (.ics)

Parse iCalendar (.ics) text into structured JSON events: summary, start/end, location, organizer, attendees, status, and RRULE. Optional bounded recurrence expansion (expand:true, capped occurrences). Deterministic, pure CPU — send the ICS text, not a URL.

Input

Field	Type	Description
ics *	string	iCalendar (.ics) text (VCALENDAR with VEVENTs)
expand	boolean	expand simple RRULEs into occurrence dates (default false)
maxOccurrences	integer	per-event expansion cap, 1-100 (default 50)

Example output

{
  "calendar": {
    "prodId": "-//Agent402//EN",
    "version": "2.0",
    "name": null,
    "timezone": null
  },
  "count": 1,
  "events": [
    {
      "uid": "demo-1",
      "summary": "Team sync",
      "location": "Zoom",
      "status": null,
      "start": {
        "iso": "2026-07-20T15:00:00Z",
        "allDay": false,
        "tzid": null
      },
      "end": {
        "iso": "2026-07-20T15:30:00Z",
        "allDay": false,
        "tzid": null
      },
      "rrule": {
        "raw": "FREQ=WEEKLY;COUNT=3",
        "freq": "WEEKLY",
        "interval": 1,
        "count": 3
      },
      "occurrences": {
        "count": 3,
        "capped": false,
        "dates": [
          "2026-07-20T15:00:00Z",
          "2026-07-27T15:00:00Z",
          "2026-08-03T15:00:00Z"
        ]
      }
    }
  ]
}

Try it — see the 402 challenge (free)

curl -i -X POST https://agent402.tools/api/ics-parse \
  -H "Content-Type: application/json" \
  -d '{"ics":"BEGIN:VCALENDAR\nPRODID:-//Agent402//EN\nVERSION:2.0\nBEGIN:VEVENT\nUID:demo-1\nSUMMARY:Team sync\nDTSTART:20260720T150000Z\nDTEND:20260720T153000Z\nLOCATION:Zoom\nRRULE:FREQ=WEEKLY;COUNT=3\nEND:VEVENT\nEND:VCALENDAR","expand":true}'

The response is HTTP 402 Payment Required with exact payment requirements. Any x402 v2 client pays automatically and retries:

Paid call (JavaScript agent)

import { wrapFetchWithPayment } from "@x402/fetch";
import { x402Client } from "@x402/core/client";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

const client = new x402Client();
registerExactEvmScheme(client, { signer: privateKeyToAccount(KEY) });
const payFetch = wrapFetchWithPayment(fetch, client);

const res = await payFetch("https://agent402.tools/api/ics-parse", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({
    "ics": "BEGIN:VCALENDAR\nPRODID:-//Agent402//EN\nVERSION:2.0\nBEGIN:VEVENT\nUID:demo-1\nSUMMARY:Team sync\nDTSTART:20260720T150000Z\nDTEND:20260720T153000Z\nLOCATION:Zoom\nRRULE:FREQ=WEEKLY;COUNT=3\nEND:VEVENT\nEND:VCALENDAR",
    "expand": true
  }),
});

No wallet? Pay with compute

This is a pure-CPU tool, so an agent without a wallet can pay with proof-of-work instead of USDC: fetch a challenge, solve the sha256 puzzle (16 leading zero bits — a fraction of a second of CPU, no money, no AI tokens), and resend with the X-Pow-Solution header.

import { createHash } from "node:crypto";
const lz = (b) => { let t = 0; for (const x of b) { if (!x) { t += 8; continue; } t += Math.clz32(x) - 24; break; } return t; };
const c = await (await fetch("https://agent402.tools/api/pow/challenge?slug=ics-parse")).json();
let n = 0;
while (lz(createHash("sha256").update(c.challenge + ":" + n).digest()) < c.difficulty) n++;
await fetch("https://agent402.tools/api/ics-parse", { method: "POST", headers: { "X-Pow-Solution": c.token + ":" + n, "Content-Type": "application/json" }, body: JSON.stringify({"ics":"BEGIN:VCALENDAR\nPRODID:-//Agent402//EN\nVERSION:2.0\nBEGIN:VEVENT\nUID:demo-1\nSUMMARY:Team sync\nDTSTART:20260720T150000Z\nDTEND:20260720T153000Z\nLOCATION:Zoom\nRRULE:FREQ=WEEKLY;COUNT=3\nEND:VEVENT\nEND:VCALENDAR","expand":true}) });

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