diff --git a/src/server/execute.ts b/src/server/execute.ts
index eac81c7..6770c5a 100644
--- a/src/server/execute.ts
+++ b/src/server/execute.ts
@@ -305,7 +305,10 @@ export async function execute(ctx: AdapterExecutionContext): Promise<AdapterExec
   const retainJobs = asBoolean(config.retainJobs, false);
   const kubeconfigPath = asString(config.kubeconfig, "") || undefined;
 
-  // Guard: claude_k8s must not run concurrently for the same agent (shared PVC/session)
+  // Guard: claude_k8s must not run concurrently for the same agent (shared PVC/session).
+  // After a server restart, orphaned K8s Jobs from previous (now-failed) runs may
+  // still be running.  We detect those by comparing the Job's run-id label against
+  // the current runId and clean them up so this execution can proceed.
   const agentId = ctx.agent.id;
   const selfPod = await getSelfPodInfo(kubeconfigPath);
   const guardNamespace = asString(config.namespace, "") || selfPod.namespace;
@@ -319,15 +322,39 @@ export async function execute(ctx: AdapterExecutionContext): Promise<AdapterExec
       (j) => !j.status?.conditions?.some((c) => (c.type === "Complete" || c.type === "Failed") && c.status === "True"),
     );
     if (running.length > 0) {
-      const names = running.map((j) => j.metadata?.name).join(", ");
-      await onLog("stderr", `[paperclip] Concurrent run blocked: existing Job(s) still running for this agent: ${names}\n`);
-      return {
-        exitCode: null,
-        signal: null,
-        timedOut: false,
-        errorMessage: `Concurrent run blocked: Job ${names} is still running for this agent`,
-        errorCode: "k8s_concurrent_run_blocked",
-      };
+      // Separate orphaned jobs (from a previous server-side run) from truly
+      // concurrent jobs (same runId — shouldn't happen but guard defensively).
+      const orphaned = running.filter(
+        (j) => (j.metadata?.labels?.["paperclip.io/run-id"] ?? "") !== runId,
+      );
+      const samRun = running.filter(
+        (j) => (j.metadata?.labels?.["paperclip.io/run-id"] ?? "") === runId,
+      );
+
+      if (orphaned.length > 0) {
+        const orphanNames = orphaned.map((j) => j.metadata?.name).join(", ");
+        await onLog("stdout", `[paperclip] Cleaning up ${orphaned.length} orphaned K8s Job(s) from previous run(s): ${orphanNames}\n`);
+        for (const j of orphaned) {
+          const name = j.metadata?.name;
+          if (name) {
+            await cleanupJob(guardNamespace, name, onLog, kubeconfigPath);
+          }
+        }
+      }
+
+      // If there are still running Jobs that belong to THIS run (shouldn't happen
+      // since we haven't created the Job yet), block execution.
+      if (samRun.length > 0) {
+        const names = samRun.map((j) => j.metadata?.name).join(", ");
+        await onLog("stderr", `[paperclip] Concurrent run blocked: existing Job(s) still running for this run: ${names}\n`);
+        return {
+          exitCode: null,
+          signal: null,
+          timedOut: false,
+          errorMessage: `Concurrent run blocked: Job ${names} is still running for this agent`,
+          errorCode: "k8s_concurrent_run_blocked",
+        };
+      }
     }
   } catch {
     // If we can't check, proceed — the heartbeat service enforces concurrency too
@@ -391,11 +418,9 @@ export async function execute(ctx: AdapterExecutionContext): Promise<AdapterExec
       podName = await waitForPod(namespace, jobName, scheduleTimeoutMs, onLog, kubeconfigPath);
       await onLog("stdout", `[paperclip] Pod running: ${podName}\n`);
 
-      // Notify the server that execution has started. Without this call,
-      // the server has no processStartedAt timestamp for the run, so the
-      // stale-run reaper (reapOrphanedRuns) cannot distinguish a live K8s
-      // job from an orphaned run and may mark it as failed — causing the
-      // UI to show no active runs and triggering duplicate run attempts.
+      // Notify the server that execution has started.  This sets
+      // processStartedAt and refreshes updatedAt in the DB, which the
+      // stale-run reaper (reapOrphanedRuns) uses to decide liveness.
       if (ctx.onSpawn) {
         await ctx.onSpawn({
           pid: -1,              // no local process; sentinel for K8s Job
@@ -424,10 +449,25 @@ export async function execute(ctx: AdapterExecutionContext): Promise<AdapterExec
     // Keepalive: periodically send a status line via onLog so the
     // Paperclip server knows the adapter is still alive even when the
     // pod produces no output (e.g. Claude is in a long thinking phase).
+    //
+    // IMPORTANT: onLog alone does NOT update the run's updatedAt in the
+    // DB — it only appends to the log store and publishes SSE events.
+    // The stale-run reaper checks updatedAt, so we must also call
+    // onSpawn periodically to refresh it.  Without this, multi-instance
+    // deployments can reap a live run from another server instance
+    // after the 5-minute staleness window.
     let lastLogAt = Date.now();
+    let keepaliveTick = 0;
     keepaliveTimer = setInterval(() => {
       const silenceSec = Math.round((Date.now() - lastLogAt) / 1000);
       void onLog("stdout", `[paperclip] keepalive — job ${jobName} running (${silenceSec}s since last output)\n`);
+
+      // Refresh updatedAt every ~4 minutes (16 ticks × 15s) to stay
+      // well within the 5-minute reaper staleness window.
+      keepaliveTick++;
+      if (ctx.onSpawn && keepaliveTick % 16 === 0) {
+        void ctx.onSpawn({ pid: -1, processGroupId: null, startedAt: new Date().toISOString() }).catch(() => {});
+      }
     }, KEEPALIVE_INTERVAL_MS);
     const wrappedOnLog: typeof onLog = async (stream, chunk) => {
       lastLogAt = Date.now();