diff --git a/scripts/scenarios/start-app.ts b/scripts/scenarios/start-app.ts
index 5dee3f26c1..b5d752809d 100644
--- a/scripts/scenarios/start-app.ts
+++ b/scripts/scenarios/start-app.ts
@@ -22,7 +22,7 @@ import { ScenarioError } from "./shell.ts";
 // The dev runner's web port is 5733 plus an offset. Mirror of BASE_WEB_PORT in dev-runner.ts.
 const BASE_WEB_PORT = 5733;
 // The replay agent `vp run dev` registers: free, recorded turns through the real adapter.
-const REPLAY = { instanceId: "devReplay", model: "showcase" };
+const REPLAY = { instanceId: "codex", model: "replay" };
 // Generated text (titles) cannot go to the replay agent: the server swaps an ACP agent for the
 // first enabled real provider, else its default, Codex. So every provider it could fall back to
 // is off and Codex is a command that only fails: no run reaches a paid model.
@@ -75,8 +75,8 @@ const prepareHome = Effect.fn("startApp.prepareHome")(function* (home: string) {
           driver,
           {
             driver,
-            enabled: false,
-            ...(driver === "codex" ? { config: { binaryPath: noModel } } : {}),
+            enabled: driver === "codex",
+            ...(driver === "codex" ? { config: { binaryPath: process.env.T3_PROOF_REPLAY_BINARY } } : {}),
           },
         ]),
       ),