diff --git a/ci/sccache_stats.sh b/ci/sccache_stats.sh
index 3a3ebc4..1e36f4c 100755
--- a/ci/sccache_stats.sh
+++ b/ci/sccache_stats.sh
@@ -1,21 +1,26 @@
 #!/bin/bash
 
 # This script prints the sccache hit rate between two calls to sccache --show-stats.
-# It should be sourced in your script before and after the operations you want to profile,
-# with the 'start' or 'end' argument respectively.
+# It must be sourced. Exits with an error if executed directly.
+
+if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
+  echo "Error: ci/sccache_stats.sh must be sourced, not executed."
+  echo "Usage: source ci/sccache_stats.sh {start|end}"
+  exit 2
+fi
 
 mode=$1
 
 if [[ "$mode" != "start" && "$mode" != "end" ]]; then
     echo "Invalid mode: $mode"
-    echo "Usage: $0 {start|end}"
-    exit 1
+    echo "Usage: source ${BASH_SOURCE[0]} {start|end}"
+    return 1
 fi
 
 # Check if sccache is available
 if ! command -v sccache &> /dev/null; then
     echo "Notice: sccache is not available. Skipping..."
-    exit 0
+    return 0
 fi
 
 case $mode in
@@ -26,7 +31,7 @@ case $mode in
   end)
     if [[ -z ${SCCACHE_START_HITS+x} || -z ${SCCACHE_START_MISSES+x} ]]; then
         echo "Error: start stats not collected. Did you call this script with 'start' before your operations?"
-        exit 1
+        return 1
     fi
 
     final_hits=$(sccache --show-stats | awk '/^[ \t]*Cache hits[ \t]+[0-9]+/ {print $3}')
@@ -35,16 +40,11 @@ case $mode in
     misses=$((final_misses - SCCACHE_START_MISSES))
     total=$((hits + misses))
 
-    prefix=""
-    if [ ${GITHUB_ACTIONS:-false} = "true" ]; then
-      prefix="::notice::"
-    fi
-
     if (( total > 0 )); then
       hit_rate=$(awk -v hits="$hits" -v total="$total" 'BEGIN { printf "%.2f", (hits / total) * 100 }')
-      echo ${prefix}"sccache hits: $hits | misses: $misses | hit rate: $hit_rate%"
+      echo "sccache hits: $hits | misses: $misses | hit rate: $hit_rate%"
     else
-      echo ${prefix}"sccache stats: N/A No new compilation requests"
+      echo "sccache stats: N/A No new compilation requests"
     fi
     unset SCCACHE_START_HITS
     unset SCCACHE_START_MISSES