diff --git a/rlm_query b/rlm_query
index 61dfb66..916d66e 100755
--- a/rlm_query
+++ b/rlm_query
@@ -165,7 +165,7 @@ fi
 # Trace logging (optional)
 # ----------------------------------------------------------------------
 if [ -n "${PI_TRACE_FILE:-}" ]; then
-    echo "[$(date +%H:%M:%S.%3N)] depth=$DEPTH→$NEXT_DEPTH PID=$$ PPID=$PPID call=$RLM_CALL_COUNT trace=$RLM_TRACE_ID fork=$FORK prompt: ${PROMPT:0:120}" >> "$PI_TRACE_FILE"
+    echo "[$(date +%H:%M:%S.%3N)] depth=${DEPTH}→${NEXT_DEPTH} PID=$$ PPID=$PPID call=$RLM_CALL_COUNT trace=$RLM_TRACE_ID fork=$FORK prompt: ${PROMPT:0:120}" >> "$PI_TRACE_FILE"
 fi
 
 # ----------------------------------------------------------------------
diff --git a/tests/test_unit.sh b/tests/test_unit.sh
index 5f9425a..0abba60 100644
--- a/tests/test_unit.sh
+++ b/tests/test_unit.sh
@@ -340,7 +340,8 @@ OUTPUT=$(
     CONTEXT="$TEST_TMP/ctx.txt" \
     rlm_query "How many r's in strawberry?"
 )
-assert_contains "T14d: prompt file is set" "RLM_PROMPT_FILE=/tmp/rlm_prompt_" "$OUTPUT"
+assert_contains "T14d: prompt file is set" "RLM_PROMPT_FILE=" "$OUTPUT"
+assert_contains "T14d: prompt file path contains rlm_prompt" "rlm_prompt_" "$OUTPUT"
 assert_contains "T14d: prompt file has content" "PROMPT_CONTENT=How many r's in strawberry?" "$OUTPUT"
 
 # ─── Test Group: Temp File Cleanup ────────────────────────────────────────
diff --git a/ypi b/ypi
index 5462c1d..7b3d525 100755
--- a/ypi
+++ b/ypi
@@ -121,7 +121,10 @@ while [[ $# -gt 0 ]]; do
 done
 # Launch Pi with the combined system prompt, passing all args through
 # User's own extensions (hashline, etc.) are discovered automatically by Pi.
+# Pass through RLM_PROVIDER/RLM_MODEL to the root session if set.
 PI_ARGV=(pi --system-prompt "$COMBINED_PROMPT")
+[ -n "${RLM_PROVIDER:-}" ] && PI_ARGV+=(--provider "$RLM_PROVIDER")
+[ -n "${RLM_MODEL:-}" ] && PI_ARGV+=(--model "$RLM_MODEL")
 [ ${#YPI_EXT_ARGS[@]} -gt 0 ] && PI_ARGV+=("${YPI_EXT_ARGS[@]}")
 [ ${#PASS_ARGS[@]} -gt 0 ] && PI_ARGV+=("${PASS_ARGS[@]}")
 exec "${PI_ARGV[@]}"