diff --git a/clearwing/observability/otel.py b/clearwing/observability/otel.py
index 25895423..65e21cb6 100644
--- a/clearwing/observability/otel.py
+++ b/clearwing/observability/otel.py
@@ -101,7 +101,7 @@ def _otlp_exporter() -> SpanExporter:
         )
         if api_key := os.environ.get("PHOENIX_API_KEY"):
             if not standard_headers_configured:
-                kwargs["headers"] = {"api_key": api_key}
+                kwargs["headers"] = {"authorization": f"Bearer {api_key}"}
         return OTLPSpanExporter(**kwargs)
     return OTLPSpanExporter()
 
diff --git a/clearwing/sourcehunt/runner.py b/clearwing/sourcehunt/runner.py
index 38327844..a45361e3 100644
--- a/clearwing/sourcehunt/runner.py
+++ b/clearwing/sourcehunt/runner.py
@@ -1233,19 +1233,23 @@ def _finalize_spend_ledger(self, status: str | None = None) -> dict[str, Any]:
         return summary
 
     def run(self) -> SourceHuntResult:
+        from clearwing.observability.otel import force_flush
         from clearwing.ui.llm_activity import llm_activity_panel
 
         self._ensure_spend_ledger()
-        with llm_activity_panel(
-            live=self._live,
-            budget_usd=self.budget_usd or None,
-            spend_ledger=self._spend_ledger,
-            trace_context=lambda: (
-                getattr(self, "_otel_trace_id", None),
-                getattr(self, "_otel_span_id", None),
-            ),
-        ):
-            return asyncio.run(self.arun())
+        try:
+            with llm_activity_panel(
+                live=self._live,
+                budget_usd=self.budget_usd or None,
+                spend_ledger=self._spend_ledger,
+                trace_context=lambda: (
+                    getattr(self, "_otel_trace_id", None),
+                    getattr(self, "_otel_span_id", None),
+                ),
+            ):
+                return asyncio.run(self.arun())
+        finally:
+            force_flush()
 
     async def _arun_proof_flow(self) -> SourceHuntResult:
         """Run the proof-carrying engine and adapt its typed output."""
diff --git a/tests/test_otel.py b/tests/test_otel.py
index 212771f2..86a6c36a 100644
--- a/tests/test_otel.py
+++ b/tests/test_otel.py
@@ -108,7 +108,7 @@ def test_standard_and_phoenix_environment_detection(monkeypatch):
     assert otel.telemetry_configured() is False
 
 
-def test_phoenix_api_key_becomes_otlp_header(monkeypatch):
+def test_phoenix_api_key_becomes_bearer_header(monkeypatch):
     monkeypatch.delenv("OTEL_EXPORTER_OTLP_ENDPOINT", raising=False)
     monkeypatch.delenv("OTEL_EXPORTER_OTLP_TRACES_ENDPOINT", raising=False)
     monkeypatch.delenv("OTEL_EXPORTER_OTLP_HEADERS", raising=False)
@@ -123,7 +123,7 @@ def test_phoenix_api_key_becomes_otlp_header(monkeypatch):
 
     exporter.assert_called_once_with(
         endpoint="https://phoenix.example/v1/traces",
-        headers={"api_key": "secret-key"},
+        headers={"authorization": "Bearer secret-key"},
     )