diff --git a/agent-ui/.sync-state.json b/agent-ui/.sync-state.json
new file mode 100644
index 0000000..e91b3ed
--- /dev/null
+++ b/agent-ui/.sync-state.json
@@ -0,0 +1,19 @@
+{
+  "schema_version": 1,
+  "surface_type": "ops-dev",
+  "baseline_mode": "migration",
+  "last_sync_mode": "baseline",
+  "last_synced_head": "bebd95f909db96413aecd6873fdfddd17bac4c74",
+  "last_synced_at": "2026-06-25T01:54:27Z",
+  "agent_ui_paths": [
+    "agent-ui/README.md",
+    "agent-ui/definition/index.md",
+    "agent-ui/definition/views",
+    "agent-ui/definition/components",
+    "agent-ui/frame/index.md"
+  ],
+  "code_paths": [],
+  "notes": [
+    "Legacy agent-ui baseline migration. No code sync performed."
+  ]
+}