diff --git a/emrg/server/daemon.py b/emrg/server/daemon.py
index 288331ae..78fca142 100644
--- a/emrg/server/daemon.py
+++ b/emrg/server/daemon.py
@@ -259,7 +259,7 @@ def __init__(self, llm_config: LlmConfig) -> None:
         # (estimated_tokens, iso_ts) at anchor-loss warning time, so the
         # estimator drift of the anchor-less window can be measured when
         # the provider re-anchors (countable metric, not just a log line).
-        self._missing_anchor_est: dict[str, tuple[int, str]] = {}
+        self._missing_anchor_est: dict[str, tuple[int, str, str]] = {}
         # Rant 2026-08-23T13:54:14: per-session dynamic-context snapshot
         # (session_id → (text, injected_ms)) so unchanged context is not
         # re-sent (context_refresh_interval_ms gating).
@@ -3023,12 +3023,18 @@ def _warn_missing_usage_anchor(
             return  # already warned once for this session
         self._warned_missing_usage_anchor.add(session.session_id)
         loss_ts = datetime.now().astimezone().isoformat()
-        self._missing_anchor_est[session.session_id] = (estimated, loss_ts)
+        # Issue #1011 (Dev.to post-3, heinrichneb): record WHICH provider went
+        # silent so cross-provider loss windows are attributable, not just
+        # countable — "a counter that can't say WHICH provider went silent is
+        # half a counter". The provider at loss time is stored so the drift
+        # measurement (possibly after a switch) can attribute both ends.
+        self._missing_anchor_est[session.session_id] = (estimated, loss_ts, self.llm.config.model)
         try:
             _append_usage_anchor_event({
                 "type": "anchor_loss",
                 "timestamp": loss_ts,
                 "session": session.session_id,
+                "provider": self.llm.config.model,
                 "est": estimated,
             })
         except OSError as exc:
@@ -3055,7 +3061,7 @@ def _record_anchor_drift(self, session, real_pt: int) -> None:
         stored = self._missing_anchor_est.pop(session.session_id, None)
         if not stored:
             return
-        est_before, loss_ts = stored
+        est_before, loss_ts, provider_at_loss = stored
         try:
             _append_usage_anchor_event({
                 "type": "anchor_drift",
@@ -3064,6 +3070,11 @@ def _record_anchor_drift(self, session, real_pt: int) -> None:
                 "real_after": real_pt,
                 "delta": real_pt - est_before,
                 "loss_ts": loss_ts,
+                # Issue #1011: attribute both ends of a cross-provider loss
+                # window (a mid-session switch deliberately drops anchors per
+                # #1003, so provider_at_loss may differ from provider_after).
+                "provider_at_loss": provider_at_loss,
+                "provider_after": self.llm.config.model,
             })
         except OSError as exc:
             logger.warning("usage-anchor stats append failed: %s", exc)
diff --git a/tests/test_daemon.py b/tests/test_daemon.py
index b7087c6c..cef013fd 100644
--- a/tests/test_daemon.py
+++ b/tests/test_daemon.py
@@ -613,7 +613,7 @@ def test_invalidate_usage_anchors_on_switch():
     server = _make_server()
     server._usage_anchors["s1"] = (222_000, 148_000)
     server._usage_anchors["s2"] = (100_000, 60_000)
-    server._missing_anchor_est["s1"] = (150_000, "2026-08-26T00:00:00+08:00")
+    server._missing_anchor_est["s1"] = (150_000, "2026-08-26T00:00:00+08:00", "gpt-4o-mini")
 
     server._invalidate_usage_anchors_on_switch()
 
@@ -710,7 +710,10 @@ def test_usage_anchor_loss_event_is_countable(tmp_path, monkeypatch):
     e1, e2 = json.loads(lines[0]), json.loads(lines[1])
     assert e1["type"] == "anchor_loss" and e1["session"] == "s1"
     assert e1["total"] == 1 and "timestamp" in e1
+    # Issue #1011: the loss event must name the provider that went silent
+    assert e1["provider"] == "gpt-4o-mini"
     assert e2["session"] == "s2" and e2["est"] == 60_000 and e2["total"] == 2
+    assert e2["provider"] == "gpt-4o-mini"
 
 
 def test_usage_anchor_stats_survive_restart(tmp_path, monkeypatch):
@@ -759,6 +762,10 @@ def test_usage_anchor_drift_measured_on_reanchor(tmp_path, monkeypatch):
     assert drift["real_after"] == 180_000
     assert drift["delta"] == 80_000
     assert drift["loss_ts"] == loss["timestamp"]
+    # Issue #1011: both ends of the loss window carry provider identity
+    assert loss["provider"] == "gpt-4o-mini"
+    assert drift["provider_at_loss"] == "gpt-4o-mini"
+    assert drift["provider_after"] == "gpt-4o-mini"
 
     # Re-anchor measured once — a second call (no pending loss) is a no-op
     server._record_anchor_drift(_SidSession(sid), 200_000)