[eric] browser: fail fast with an honest message when the card's webview is gone

backend/apps/agents/browser/browser_agent.py

@@ -30,7 +30,9 @@ from backend.apps.agents.browser.browser_loop import (
     _LOOP_WINDOW_SIZE,
     _detect_loop,
     _hash_tool_call,
+    _CARD_GONE_LIMIT,
     advance_stagnation,
+    card_is_unavailable,
     completion_is_honest,
     stagnation_exhausted,
 )
@@ -320,6 +322,7 @@ async def run_browser_agent(
     # Loop detection state; sliding window of recent state-mutating tool calls
     recent_tool_calls: list[tuple[str, str, str]] = []
     loop_trigger_count = 0
+    card_gone_streak = 0  # consecutive "card is gone" results -> fail fast, don't spin
 
     # Stagnation state: busy-but-stuck detection (no URL change + failures
     # across a run of actions), distinct from the exact-repeat loop above.
@@ -836,6 +839,7 @@ async def run_browser_agent(
                 })
                 if result.get("url"):
                     last_seen_url = result["url"]
+                card_gone_streak = card_gone_streak + 1 if card_is_unavailable(result) else 0
 
                 if tu.name == "BrowserScreenshot" and result.get("image"):
                     final_screenshot = result["image"]
@@ -949,6 +953,15 @@ async def run_browser_agent(
                 )
                 break
 
+            # The card's webview is gone (closed / dashboard not open). The agent
+            # can't bring it back, so stop retrying and report it honestly below.
+            if card_gone_streak >= _CARD_GONE_LIMIT:
+                logger.warning(
+                    f"[browser-agent {session_id}] browser card {browser_id} is gone "
+                    f"({card_gone_streak} consecutive misses); aborting fast"
+                )
+                break
+
         if cancel_event.is_set():
             session.status = "stopped"
             browser_metrics.record_task(session_id, browser_id, task, "stopped",
@@ -991,8 +1004,12 @@ async def run_browser_agent(
 
         # Honesty gate: the model declaring done is not proof the goal happened.
         # If the run did no real work (zero actions, all actions errored, or only
-        # looked around), report the truth instead of a ghost "completed".
-        honest, dishonest_reason = completion_is_honest(action_log)
+        # looked around), report the truth instead of a ghost "completed". A gone
+        # card gets its own precise reason instead of the generic verdict.
+        if card_gone_streak >= _CARD_GONE_LIMIT:
+            honest, dishonest_reason = False, "the browser card is no longer open (it was closed or never opened)"
+        else:
+            honest, dishonest_reason = completion_is_honest(action_log)
         final_status = "completed" if honest else "error"
         if not honest:
             summary = f"I was not able to complete this task ({dishonest_reason})."

backend/apps/agents/browser/browser_loop.py

@@ -199,6 +199,20 @@ _READ_TOOLS = {
 }
 
 
+# A card whose webview is gone is UNRECOVERABLE by the agent (it cannot resurrect
+# the card), unlike a missing selector it could route around. The frontend
+# returns these only AFTER a 2s re-register grace, so they mean the card is truly
+# gone (closed) or the dashboard was never open. Retrying just burns the turn
+# budget (the multi-minute spins we measured), so the caller fails fast instead.
+_CARD_GONE_MARKERS = ("not an electron webview", "no dashboard is connected")
+_CARD_GONE_LIMIT = 2  # consecutive misses before we give up (absorbs a transient)
+
+
+def card_is_unavailable(result: dict) -> bool:
+    err = str(result.get("error") or "").lower()
+    return any(m in err for m in _CARD_GONE_MARKERS)
+
+
 def completion_is_honest(action_log: list[dict]) -> tuple[bool, str]:
     """Reality-check a run the model declared done. Returns (honest, reason).
 

backend/tests/test_browser_agent_loop.py

@@ -394,6 +394,41 @@ def test_ghost_completion_is_reported_as_error_not_completed(monkeypatch):
     assert SK.find_skill("docs.google.com", "Submit the form") is None
 
 
+def test_dead_browser_card_aborts_fast_without_spinning(monkeypatch):
+    # The measured waste: a sub-agent dispatched to a released card retried the
+    # dead webview for many turns. Now a gone card must abort fast (a couple of
+    # turns, not the whole budget) and report the precise reason.
+    import backend.apps.agents.browser.browser_skills as SK
+    SK.clear()
+    BH._browser_history.clear()
+    # the model would happily keep clicking for 8 turns if we let it
+    primary = FakeLLM(
+        [Resp([_rp("click"), _tu("BrowserClick", selector=f".s{i}")]) for i in range(8)]
+        + [Resp([Blk("text", "done")], stop_reason="end_turn")]
+    )
+    aux = FakeAux()
+    _install(monkeypatch, primary, aux)
+
+    async def _card_gone(request_id, action, browser_id, params, tab_id=""):
+        return {"error": f"Browser card '{browser_id}' not found or not an Electron webview"}
+    monkeypatch.setattr(BA.ws_manager, "send_browser_command", _card_gone, raising=False)
+    captured = {}
+    orig = BA.ws_manager.send_to_session
+
+    async def _cap(session_id, event, payload):
+        if event == "agent:status":
+            captured["status"] = payload.get("status")
+        return await orig(session_id, event, payload)
+    monkeypatch.setattr(BA.ws_manager, "send_to_session", _cap, raising=False)
+
+    r = asyncio.run(BA.run_browser_agent(
+        task="Click submit", browser_id="b1", model="sonnet", initial_url=DOC_URL,
+    ))
+    assert len(primary.calls) <= 3, "a dead card must fail fast, not spin the whole budget"
+    assert captured.get("status") == "error"
+    assert "no longer open" in r["summary"].lower()
+
+
 def test_perception_is_frontloaded_into_first_turn(monkeypatch):
     # With a known start URL, the agent should prefetch the element list + page
     # text and put them in the FIRST user message, so the model can act on turn 1

backend/tests/test_browser_stagnation.py

@@ -5,6 +5,7 @@ from backend.apps.agents.browser.browser_loop import (
     _STAGNATION_MAX,
     _looks_like_failure,
     advance_stagnation,
+    card_is_unavailable,
     completion_is_honest,
     is_unproductive,
     stagnation_exhausted,
@@ -151,3 +152,11 @@ def test_completion_honest_when_some_errors_but_an_action_landed():
     log = [_err("BrowserClick"), _err("BrowserClick"), _ok("BrowserClickIndex", "Clicked Submit")]
     honest, reason = completion_is_honest(log)
     assert honest
+
+
+def test_card_is_unavailable_only_for_unrecoverable_errors():
+    # a gone card is unrecoverable (fail fast); a missing selector is not (route around)
+    assert card_is_unavailable({"error": "Browser card 'b1' not found or not an Electron webview"})
+    assert card_is_unavailable({"error": "No dashboard is connected. Open the dashboard to use browser tools."})
+    assert not card_is_unavailable({"error": "Element not found: '.submit'"})
+    assert not card_is_unavailable({"text": "ok", "url": "http://x"})