diff --git a/src/presence/heartbeat.ts b/src/presence/heartbeat.ts
new file mode 100644
index 0000000..a718a08
--- /dev/null
+++ b/src/presence/heartbeat.ts
@@ -0,0 +1,25 @@
+import { prisma } from '../prisma.js'
+
+export function startHeartbeat(opts: {
+  tokenId: string
+  intervalMs?: number
+}): { stop: () => void } {
+  const ms = opts.intervalMs ?? 5_000
+
+  const timer = setInterval(async () => {
+    try {
+      const result = await prisma.claudeWorker.updateMany({
+        where: { token_id: opts.tokenId },
+        data: { last_seen_at: new Date() },
+      })
+      if (result.count === 0) {
+        console.warn('[scrum4me-mcp] heartbeat: worker record not found — token may be revoked, stopping heartbeat')
+        clearInterval(timer)
+      }
+    } catch (err) {
+      console.warn('[scrum4me-mcp] heartbeat error:', err)
+    }
+  }, ms)
+
+  return { stop: () => clearInterval(timer) }
+}