diff --git a/lib/services/harness-compose.test.ts b/lib/services/harness-compose.test.ts
index 66035ca..2444389 100644
--- a/lib/services/harness-compose.test.ts
+++ b/lib/services/harness-compose.test.ts
@@ -98,6 +98,7 @@ describe('generateStandaloneCompose', () => {
       expect(result).toContain('ENABLE_VNC=true')
       expect(result).toContain('VNC_BIND=0.0.0.0')
       expect(result).toContain('VNC_RESOLUTION=1280x720')
+      expect(result).toContain('BROWSER_IDLE_TIMEOUT_MS=3600000')
       expect(result).toContain('CAMOFOX_PORT=9377')
     })
 
diff --git a/lib/services/harness-compose.ts b/lib/services/harness-compose.ts
index b37c079..0dcaca9 100644
--- a/lib/services/harness-compose.ts
+++ b/lib/services/harness-compose.ts
@@ -265,6 +265,10 @@ services:
       - ENABLE_VNC=true
       - VNC_BIND=0.0.0.0
       - VNC_RESOLUTION=1280x720
+      # Human-in-the-loop flows (VNC checkout/login handoff) generate no API
+      # activity, and the camofox server's 5-minute default reaps the browser
+      # mid-payment. One hour keeps sessions alive across a human handoff.
+      - BROWSER_IDLE_TIMEOUT_MS=3600000
     volumes:
       - ${agentDataDir}/.camofox:/data
 ${ollamaBlock}