diff --git a/e2e/agentnetwork/custom_pricing_test.go b/e2e/agentnetwork/custom_pricing_test.go
index 2fe093602..b3ca5028f 100644
--- a/e2e/agentnetwork/custom_pricing_test.go
+++ b/e2e/agentnetwork/custom_pricing_test.go
@@ -446,10 +446,10 @@ func TestPriceChangeUpdatesRecordedCost(t *testing.T) {
 		}
 		row, ok := lookupAccessLogBySession(repriceCtx, lastSession, repriceIngestWindow)
 		if !ok {
-			// No row for this request. The provider update rebuilds the proxy's
-			// middleware chain, and a request served mid-rebuild can complete
-			// without a resolved provider — 200 to the caller, nothing to
-			// attribute, so no row is ever written for it. Fire another one.
+			// No row for this request. The proxy now publishes a rebuilt chain
+			// before the route that reaches it, so a request can no longer be
+			// served unattributed mid-update; this retry covers the ingest
+			// window alone. Fire another one under a fresh session.
 			t.Logf("no access-log row for session %q within %s; retrying under a fresh session", lastSession, repriceIngestWindow)
 			continue
 		}
diff --git a/proxy/server.go b/proxy/server.go
index bd70b7e70..2a62db421 100644
--- a/proxy/server.go
+++ b/proxy/server.go
@@ -2074,9 +2074,15 @@ func (s *Server) updateMapping(ctx context.Context, mapping *proto.ProxyMapping)
 		return fmt.Errorf("auth setup for domain %s: %w", mapping.GetDomain(), err)
 	}
 	m := s.protoToMapping(ctx, mapping)
-	s.proxy.AddMapping(m)
-	s.meter.AddMapping(m)
+	// The chain is published before the route that leads to it. A request
+	// arriving at a target whose chain has not been rebuilt yet is served
+	// straight through, so a provider update that added the route first left a
+	// window in which an inference could complete unrouted and unmetered.
+	// Rebuilding first inverts that: the worst a request in the window meets is
+	// the new chain in front of the previous target, which is still counted.
 	s.rebuildMiddlewareChains(svcID, m)
+	s.meter.AddMapping(m)
+	s.proxy.AddMapping(m)
 	return nil
 }