diff --git a/apps/web/lib/active-runs.ts b/apps/web/lib/active-runs.ts
index 182ee4bfbcb..58168455ca8 100644
--- a/apps/web/lib/active-runs.ts
+++ b/apps/web/lib/active-runs.ts
@@ -356,12 +356,35 @@ function updateIndex(
 ) {
 	try {
 		const idxPath = indexFile();
-		if (!existsSync(idxPath)) {return;}
-		const index = JSON.parse(
+		let index: Array<Record<string, unknown>>;
+		if (!existsSync(idxPath)) {
+			// Auto-create index with a bootstrap entry for this session so
+			// orphaned .jsonl files become visible in the sidebar.
+			index = [{
+				id: sessionId,
+				title: opts.title || "New Chat",
+				createdAt: Date.now(),
+				updatedAt: Date.now(),
+				messageCount: opts.incrementCount || 0,
+			}];
+			writeFileSync(idxPath, JSON.stringify(index, null, 2));
+			return;
+		}
+		index = JSON.parse(
 			readFileSync(idxPath, "utf-8"),
 		) as Array<Record<string, unknown>>;
-		const session = index.find((s) => s.id === sessionId);
-		if (!session) {return;}
+		let session = index.find((s) => s.id === sessionId);
+		if (!session) {
+			// Session file exists but wasn't indexed — add it.
+			session = {
+				id: sessionId,
+				title: opts.title || "New Chat",
+				createdAt: Date.now(),
+				updatedAt: Date.now(),
+				messageCount: 0,
+			};
+			index.unshift(session);
+		}
 		session.updatedAt = Date.now();
 		if (opts.incrementCount) {
 			session.messageCount =