diff --git a/src/wifi/model/wifi-phy.cc b/src/wifi/model/wifi-phy.cc
index b4cc8a5cf8..23658b812c 100644
--- a/src/wifi/model/wifi-phy.cc
+++ b/src/wifi/model/wifi-phy.cc
@@ -302,15 +302,19 @@ WifiPhy::GetTypeId()
             .AddTraceSource(
                 "PhyTxBegin",
                 "Trace source indicating a packet has begun transmitting over the medium; "
-                "the packet is a single MPDU even if the MPDU is transmitted within an A-MPDU.",
+                "the packet holds a single MPDU even if the MPDU is transmitted within an A-MPDU "
+                "(in which case this trace fires for each MPDU in the "
+                "A-MPDU).",
                 MakeTraceSourceAccessor(&WifiPhy::m_phyTxBeginTrace),
                 "ns3::WifiPhy::PhyTxBeginTracedCallback")
-            .AddTraceSource("PhyTxPsduBegin",
-                            "Trace source indicating a PSDU (in the case of SU PPDU), "
-                            "or a PSDU map (in the case of MU PPDU), "
-                            "has begun transmitting over the channel medium",
-                            MakeTraceSourceAccessor(&WifiPhy::m_phyTxPsduBeginTrace),
-                            "ns3::WifiPhy::PsduTxBeginCallback")
+            .AddTraceSource(
+                "PhyTxPsduBegin",
+                "Trace source indicating a PSDU has begun transmitting over the channel medium; "
+                "this trace returns a WifiConstPsduMap with a single element (in the case of SU "
+                "PPDU) "
+                "or multiple elements (in the case of MU PPDU)",
+                MakeTraceSourceAccessor(&WifiPhy::m_phyTxPsduBeginTrace),
+                "ns3::WifiPhy::PsduTxBeginCallback")
             .AddTraceSource("PhyTxEnd",
                             "Trace source indicating a packet "
                             "has been completely transmitted over the channel.",