diff --git a/src/lib/chatApi.ts b/src/lib/chatApi.ts
index d025002..0caae22 100644
--- a/src/lib/chatApi.ts
+++ b/src/lib/chatApi.ts
@@ -41,19 +41,29 @@ async function ensureInbox(inboxKey: string, email: string, signal?: AbortSignal
     const head = await fetch(`${api.config.baseUrl}/api/ea2/flow/${inboxKey}`, { headers: authHeaders(), signal });
     if (head.ok) return true;
   } catch { /* fall through */ }
-  const created = await fetch(`${api.config.baseUrl}/api/ea2/flow`, {
+  const body = {
+    request_id: newRequestId(),
+    ops: [
+      {
+        op: "create",
+        coll: "flow",
+        data: {
+          _key: inboxKey,
+          kind: "value",
+          status: "published",
+          name: inboxKey,
+          display_name: `Inbox · ${email}`,
+          description: `Chat inbox anchor for ${email}`,
+          source_context: "CANVAS_CHAT_INBOX",
+          config: { chat: { owner_email: email } },
+        },
+      },
+    ],
+  };
+  const created = await fetch(`${api.config.baseUrl}/api/ea2/apply-batch`, {
     method: "POST",
     headers: authHeaders(),
-    body: JSON.stringify({
-      _key: inboxKey,
-      kind: "value",
-      status: "published",
-      name: inboxKey,
-      display_name: `Inbox · ${email}`,
-      description: `Chat inbox anchor for ${email}`,
-      source_context: "CANVAS_CHAT_INBOX",
-      config: { chat: { owner_email: email } },
-    }),
+    body: JSON.stringify(body),
     signal,
   });
   return created.ok || created.status === 409;