[eric] browser: a run reports its call counts beside the prose, so a caller can check instead of trust (ENG-297)

backend/apps/agents/browser/browser_agent.py

@@ -47,6 +47,7 @@ from backend.apps.agents.browser.browser_loop import (
     deliverable_is_informational,
     interstitial_dismiss_target,
     is_mutation_task,
+    outcome_facts,
     is_publish_task,
     is_removal_task,
     recoverable_tool_error,
@@ -3275,6 +3276,9 @@ async def run_browser_agent(
             # surface the honest failure to the parent so it doesn't treat a did-nothing run as a success it can build on
             **({} if honest else {"error": summary}),
             "action_log": action_log,
+            # Counts beside the prose, so a caller can reject a "completed" that mutated nothing
+            # without parsing the summary or eyeballing the action list (ENG-297).
+            "outcome": outcome_facts(action_log),
             "final_screenshot": final_screenshot,
         }
 

backend/apps/agents/browser/browser_loop.py

@@ -414,6 +414,31 @@ P_FABRICATED_CALL_RE = re.compile(
     r"<\s*(?:antml:)?tool_use\s+", re.I)
 
 
+def outcome_facts(action_log: list[dict]) -> dict:
+    """What the run actually did, in counts a caller can check without reading the prose.
+
+    The six bad dispatches in ENG-297 were only caught because a human noticed "3 read-only calls"
+    under a "Task completed." That is a suspicious reader applying a heuristic, and a less suspicious
+    pass ships the fabrication onward. These counts travel WITH the summary so a calling agent can
+    distrust prose on principle instead of by intuition.
+
+    Every key is always present, including zeros: a missing key makes a caller's check pass silently,
+    which is the failure mode this exists to remove.
+    """
+    log = action_log or []
+    mutations = [a for a in log if a.get("tool") in P_PRODUCTIVE_TOOLS]
+    return {
+        "calls": len(log),
+        "mutations_attempted": len(mutations),
+        "mutations_succeeded": len([a for a in mutations if a.get("ok")]),
+        "reads_with_content": len([
+            a for a in log
+            if a.get("tool") in P_READ_TOOLS and a.get("ok")
+            and str(a.get("result_summary") or "").strip()
+        ]),
+    }
+
+
 def summary_fabricates_tool_calls(summary: str) -> bool:
     """True when a run's summary contains tool-call MARKUP rather than a report.
 

backend/tests/test_browser_completion_honesty.py

@@ -7,6 +7,7 @@ Run:
 from backend.apps.agents.browser.browser_loop import (
     completion_is_honest,
     is_mutation_task,
+    outcome_facts,
     summary_fabricates_tool_calls,
 )
 
@@ -119,3 +120,44 @@ def test_a_fabricating_run_cannot_report_completed():
         log, summary='<invoke name="BrowserEvaluate">{"script":"editor.getValue()"}</invoke>')
     assert not honest, "a summary that faked tool calls was reported as a completion"
     assert "fabricat" in reason.lower(), reason
+
+
+# --- Gate 2 (ENG-297): the caller needs facts it can check, not prose it must trust. ---
+#
+# The only reason any of the six bad dispatches was caught is that a human read the "Actions taken"
+# list and noticed 3 read-only calls under a "Task completed." That is a manual heuristic applied by
+# a suspicious reader. A calling agent should be able to distrust prose on principle, which means
+# the counts have to arrive beside it in a shape nothing can narrate its way around.
+
+
+def p_err(tool):
+    return {"tool": tool, "ok": False, "result_summary": ""}
+
+
+def test_outcome_facts_counts_what_actually_happened():
+    log = [
+        p_ok("BrowserGetText", "function doPost() {"),
+        p_ok("BrowserClickIndex", "Clicked"),
+        p_err("BrowserType"),
+        p_ok("BrowserScreenshot", "captured"),
+    ]
+    f = outcome_facts(log)
+    assert f["calls"] == 4, f
+    assert f["mutations_attempted"] == 2, f      # ClickIndex + Type
+    assert f["mutations_succeeded"] == 1, f      # Type failed
+    assert f["reads_with_content"] == 2, f
+
+
+def test_outcome_facts_expose_the_ghost_shape():
+    """The dispatch-5 shape: reads only. A caller can reject this without reading a word."""
+    log = [p_ok("BrowserGetText", "x"), p_ok("BrowserListInteractives", "y"), p_ok("BrowserScreenshot", "z")]
+    f = outcome_facts(log)
+    assert f["mutations_attempted"] == 0 and f["mutations_succeeded"] == 0, f
+    assert f["reads_with_content"] == 3, f
+
+
+def test_outcome_facts_on_an_empty_run_are_all_zero_not_missing():
+    """Absent keys would make a caller's check silently pass; zeros make it fail honestly."""
+    f = outcome_facts([])
+    for k in ("calls", "mutations_attempted", "mutations_succeeded", "reads_with_content"):
+        assert f[k] == 0, f"{k} missing or non-zero on an empty run: {f}"