fix(agents): prevent lost subagent findings and warn on unfiled reports

In multi-agent pentests (e.g. Issue #1439 against DVWA), subagents frequently
discover exploitable vulnerabilities and supply them as narrative strings in
agent_finish(findings=[...]) without first calling create_vulnerability_report.
Because parent agents strictly rely on filed_report_ids from authoritative state
and avoid refiling from narrative text, these findings are silently dropped,
causing scans of vulnerable targets to complete with 0 findings.

1. In child_initial_input, explicitly instruct subagents to file confirmed
   vulnerabilities via create_vulnerability_report before calling agent_finish,
   clarifying that passing findings to agent_finish does not persist reports.
2. In agent_finish, when findings is non-empty but filed_report_ids is empty,
   attach an explicit warning to the tool response payload and the rendered
   completion report delivered to the parent inbox.
3. Add regression tests in test_agent_graph_coordination.py and test_inputs.py.

strix/core/inputs.py

@@ -364,8 +364,10 @@ def child_initial_input(
         )
     parts.append(
         f"You are agent {name} ({child_id}); your parent is {parent_id}. "
-        "Maintain your own identity. Call agent_finish when your task "
-        "is complete.",
+        "Maintain your own identity. File any confirmed vulnerabilities using "
+        "create_vulnerability_report (or create_dependency_report) BEFORE calling "
+        "agent_finish — passing findings to agent_finish does not file reports. "
+        "Call agent_finish when your task is complete.",
     )
     parts.append(task)
     return [{"role": "user", "content": "\n\n".join(parts)}]

strix/tools/agents_graph/tools.py

@@ -101,6 +101,12 @@ def _render_completion_report(
         lines.extend(_render_filed_report(r) for r in filed_reports)
     else:
         lines.append("- (none)")
+        if findings:
+            lines.append(
+                "  [WARNING: This agent reported narrative findings above but filed 0 "
+                "authoritative vulnerability reports. Unreported findings are not included "
+                "in scan results or SARIF unless filed via create_vulnerability_report.]"
+            )
     lines.append("")
     lines.append("Open items (unresolved, need follow-up):")
     if open_items:
@@ -693,6 +699,7 @@ async def agent_finish(
 
     filed_reports = _filed_reports_by(me)
     filed_report_ids = [str(r.get("id")) for r in filed_reports]
+    unfiled_findings = bool((findings or []) and not filed_report_ids)
 
     parent_notified = False
     if report_to_parent and await coordinator.claim_parent_notice(me):
@@ -718,6 +725,7 @@ async def agent_finish(
                 "type": "completion",
                 "priority": "high",
                 "filed_report_ids": filed_report_ids,
+                "unfiled_findings": unfiled_findings,
             },
         )
         parent_notified = True
@@ -735,19 +743,33 @@ async def agent_finish(
         len(filed_report_ids),
         parent_notified,
     )
+    if unfiled_findings:
+        logger.warning(
+            "agent_finish: %s reported %d narrative finding(s) but filed 0 vulnerability reports",
+            me,
+            len(findings or []),
+        )
+
+    response_payload: dict[str, Any] = {
+        "success": True,
+        "agent_completed": True,
+        "parent_notified": parent_notified,
+        "agent_id": me,
+        "summary": result_summary,
+        "filed_report_ids": filed_report_ids,
+        "findings_count": len(findings or []),
+        "open_items_count": len(open_items or []),
+        "has_recommendations": bool(final_recommendations),
+    }
+    if unfiled_findings:
+        response_payload["warning"] = (
+            f"Reported {len(findings or [])} finding(s) but filed 0 vulnerability reports. "
+            "Narrative findings in agent_finish do not register vulnerabilities in the scan "
+            "report. Verified findings must be filed via create_vulnerability_report."
+        )
 
     return json.dumps(
-        {
-            "success": True,
-            "agent_completed": True,
-            "parent_notified": parent_notified,
-            "agent_id": me,
-            "summary": result_summary,
-            "filed_report_ids": filed_report_ids,
-            "findings_count": len(findings or []),
-            "open_items_count": len(open_items or []),
-            "has_recommendations": bool(final_recommendations),
-        },
+        response_payload,
         ensure_ascii=False,
         default=str,
     )

tests/test_agent_graph_coordination.py

@@ -256,3 +256,33 @@ async def test_agent_finish_without_report_state_still_completes() -> None:
 
     assert result["success"] is True
     assert result["filed_report_ids"] == []
+
+
+@pytest.mark.asyncio
+@pytest.mark.usefixtures("report_state")
+async def test_agent_finish_warns_when_findings_reported_without_filing() -> None:
+    coordinator = await _graph(interactive=False)
+
+    result = await _call(
+        agent_finish,
+        coordinator,
+        "child",
+        {
+            "result_summary": "discovered injection",
+            "findings": ["SQL injection on /login.php"],
+        },
+        parent_id="root",
+    )
+
+    assert result["success"] is True
+    assert result["filed_report_ids"] == []
+    assert "warning" in result
+    assert "Reported 1 finding(s) but filed 0 vulnerability reports" in result["warning"]
+
+    delivered = coordinator.runtimes["root"].mailbox
+    assert len(delivered) == 1
+    assert delivered[0]["unfiled_findings"] is True
+    body = delivered[0]["content"]
+    assert "authoritative vulnerability reports" in body
+    assert "create_vulnerability_report" in body
+

tests/test_inputs.py

@@ -35,6 +35,7 @@ def test_child_initial_input_single_message_without_history() -> None:
     content = result[0]["content"]
     assert "agent scout (agent-2)" in content
     assert "Audit the login flow." in content
+    assert "create_vulnerability_report" in content
     assert "Inherited context" not in content
 
 
@@ -49,6 +50,7 @@ def test_child_initial_input_single_message_with_history() -> None:
     assert "previous work" in content
     assert "agent scout (agent-2)" in content
     assert "Audit the login flow." in content
+    assert "create_vulnerability_report" in content
 
 
 @pytest.mark.parametrize(