Wake your agent when replies arrive

{
  "id": "evt_5f0c…",
  "type": "replies.waiting",
  "created_at": "2026-10-16T07:02:00.000Z",
  "workspace": { "id": "8c1e…", "name": "Acme outbound" },
  "replies": [
    {
      "id": "3d9a…",
      "from": "pia@slalom.agency",
      "subject": "Re: Quick question, Pia",
      "received_at": "2026-10-16T06:58:41.000Z",
      "sequence_id": "b71f…"
    }
  ],
  "inbox_url": "https://meerko.ai/app/inbox"
}

import { createHmac, timingSafeEqual } from "node:crypto";
import { createServer } from "node:http";
import { query } from "@anthropic-ai/claude-agent-sdk";
const SECRET = process.env.MEERKO_WEBHOOK_SECRET!; // whsec_… from Settings
const KEY = process.env.MEERKO_DRAFTS_KEY!; // a drafts-only mk_ key
function verified(header: string, body: string) {
  const { t, v1 } = Object.fromEntries(header.split(",").map((p) => p.split("=")));
  if (!t || !v1 || Math.abs(Date.now() / 1000 - Number(t)) > 300) return false;
  const expected = createHmac("sha256", SECRET).update(`${t}.${body}`).digest("hex");
  return v1.length === expected.length && timingSafeEqual(Buffer.from(v1), Buffer.from(expected));
}
createServer(async (req, res) => {
  let body = "";
  for await (const chunk of req) body += chunk;
  if (!verified(String(req.headers["meerko-signature"] ?? ""), body)) return res.writeHead(401).end();
  res.writeHead(200).end(); // answer at once: Meerko waits 10 seconds at most
  if (JSON.parse(body).type !== "replies.waiting") return;
  for await (const message of query({
    prompt: "New replies arrived in Meerko. Classify each unclassified reply and draft answers for interested ones and questions. Never approve or send.",
    options: {
      mcpServers: { meerko: { type: "http", url: "https://api.meerko.ai/mcp/drafter", headers: { authorization: `Bearer ${KEY}` } } },
      allowedTools: ["mcp__meerko__*"],
    },
  })) {
    if (message.type === "result") console.log(message.subtype);
  }
}).listen(8080);