diff --git a/worker.js b/worker.js
new file mode 100644
index 0000000..58c773c
--- /dev/null
+++ b/worker.js
@@ -0,0 +1,127 @@
+/**
+ * @typedef {object} Env
+ * @property {string} ROUTINE_FIRE_URL    - secret: Anthropic /fire endpoint URL
+ * @property {string} ROUTINE_FIRE_TOKEN  - secret: per-routine bearer token (sk-ant-oat01-...)
+ * @property {string} [TEXT_TEMPLATE]     - plain var: prompt template, supports {LocalTime} {Cron} {ISO}
+ * @property {string} [TZ]                - plain var: IANA tz, default 'UTC'
+ */
+
+/**
+ * @typedef {object} FireResponse
+ * @property {string} type
+ * @property {string} claude_code_session_id
+ * @property {string} claude_code_session_url
+ */
+
+const HEADER_VERSION = '2023-06-01';
+const HEADER_BETA = 'experimental-cc-routine-2026-04-01';
+const DEFAULT_TEMPLATE = 'Scheduled trigger at {LocalTime}';
+const DEFAULT_TZ = 'UTC';
+
+/**
+ * Substitutes `{Key}` tokens in template. Unknown tokens left intact and warn-logged.
+ * @param {string} template
+ * @param {Record<string, string>} vars
+ * @returns {string}
+ */
+export function renderText(template, vars) {
+  return template.replace(/\{(\w+)\}/g, (match, key) => {
+    if (Object.prototype.hasOwnProperty.call(vars, key)) {
+      return vars[key];
+    }
+    return match;
+  });
+}
+
+/**
+ * Formats a Date as `YYYY-MM-DD HH:mm ZZZ` in the given IANA timezone.
+ * @param {Date} date
+ * @param {string} tz
+ * @returns {string}
+ */
+export function formatLocalTime(date, tz) {
+  const fmt = new Intl.DateTimeFormat('en-CA', {
+    timeZone: tz,
+    year: 'numeric', month: '2-digit', day: '2-digit',
+    hour: '2-digit', minute: '2-digit', hour12: false,
+    timeZoneName: 'short',
+  });
+  const parts = Object.fromEntries(fmt.formatToParts(date).map(p => [p.type, p.value]));
+  return `${parts.year}-${parts.month}-${parts.day} ${parts.hour}:${parts.minute} ${parts.timeZoneName}`;
+}
+
+/**
+ * POSTs to the Claude Code routine /fire endpoint. Logs structured JSON.
+ * Never throws — network/HTTP failures are logged at error level so the
+ * Worker doesn't crash and CF doesn't retry (each /fire = new session).
+ *
+ * @param {Env} env
+ * @param {{ cron: string, scheduledTime: number }} controller
+ * @returns {Promise<void>}
+ */
+export async function fireRoutine(env, controller) {
+  const cron = controller.cron;
+  const tz = env.TZ ?? DEFAULT_TZ;
+  const template = env.TEXT_TEMPLATE ?? DEFAULT_TEMPLATE;
+  const now = new Date(controller.scheduledTime);
+
+  const text = renderText(template, {
+    ISO: now.toISOString(),
+    LocalTime: formatLocalTime(now, tz),
+    Cron: cron,
+  });
+
+  let resp;
+  try {
+    resp = await fetch(env.ROUTINE_FIRE_URL, {
+      method: 'POST',
+      headers: {
+        'Authorization': `Bearer ${env.ROUTINE_FIRE_TOKEN}`,
+        'anthropic-version': HEADER_VERSION,
+        'anthropic-beta': HEADER_BETA,
+        'Content-Type': 'application/json',
+      },
+      body: JSON.stringify({ text }),
+    });
+  } catch (err) {
+    console.log(JSON.stringify({
+      level: 'error', msg: 'fire request failed', cron,
+      err: err instanceof Error ? err.message : String(err),
+    }));
+    return;
+  }
+
+  const respBody = await resp.text();
+  if (!resp.ok) {
+    console.log(JSON.stringify({
+      level: 'error', msg: 'fire non-2xx response',
+      cron, status: resp.status, body: respBody,
+    }));
+    return;
+  }
+
+  /** @type {FireResponse | null} */
+  let parsed = null;
+  try {
+    parsed = JSON.parse(respBody);
+  } catch {
+    console.log(JSON.stringify({
+      level: 'warn', msg: 'fire 2xx but body unparseable',
+      cron, status: resp.status, body: respBody,
+    }));
+    return;
+  }
+
+  console.log(JSON.stringify({
+    level: 'info', msg: 'fire ok', cron,
+    session_url: parsed?.claude_code_session_url,
+    session_id: parsed?.claude_code_session_id,
+  }));
+}
+
+/** @type {ExportedHandler<Env>} */
+export default {
+  async scheduled(controller, env, ctx) {
+    ctx.waitUntil(fireRoutine(env, controller));
+  },
+};