diff --git a/tools/ngcp-api.inc b/tools/ngcp-api.inc
index 69291e9a8d..4e2ec83d90 100644
--- a/tools/ngcp-api.inc
+++ b/tools/ngcp-api.inc
@@ -3,6 +3,13 @@
 set -e
 
 importcreds () {
+  local CREDS=$1
+
+  if [ -z "${CREDS}" ]; then
+    echo "Error: missing mandatory file name to read" >&2
+    exit 1
+  fi
+
   if [ ! -f "${CREDS}" ]; then
     return
   fi
diff --git a/tools_bin/ngcp-api-delete b/tools_bin/ngcp-api-delete
index 94c0249e00..eaef3a77d7 100755
--- a/tools_bin/ngcp-api-delete
+++ b/tools_bin/ngcp-api-delete
@@ -19,7 +19,7 @@ EOF
 if [ -z "$APIUSER" ] ; then
 	if [ -f "$TOOLS" ] ; then
 		source "$TOOLS"
-		importcreds
+		importcreds "$CREDS"
 	else
 		APIUSER="administrator:administrator"
 	fi
diff --git a/tools_bin/ngcp-api-get b/tools_bin/ngcp-api-get
index 276330bb74..ddbc91dca2 100755
--- a/tools_bin/ngcp-api-get
+++ b/tools_bin/ngcp-api-get
@@ -19,7 +19,7 @@ EOF
 if [ -z "$APIUSER" ] ; then
 	if [ -f "$TOOLS" ] ; then
 		source "$TOOLS"
-		importcreds
+		importcreds "$CREDS"
 	else
 		APIUSER="administrator:administrator"
 	fi
diff --git a/tools_bin/ngcp-api-patch b/tools_bin/ngcp-api-patch
index fbd9794570..045d3fa870 100755
--- a/tools_bin/ngcp-api-patch
+++ b/tools_bin/ngcp-api-patch
@@ -21,7 +21,7 @@ EOF
 if [ -z "$APIUSER" ] ; then
   if [ -f "$TOOLS" ] ; then
     source "$TOOLS"
-    importcreds
+    importcreds "$CREDS"
   else
     APIUSER="administrator:administrator"
   fi
diff --git a/tools_bin/ngcp-api-post b/tools_bin/ngcp-api-post
index b739df5623..5c0e74200f 100755
--- a/tools_bin/ngcp-api-post
+++ b/tools_bin/ngcp-api-post
@@ -20,7 +20,7 @@ EOF
 if [ -z "$APIUSER" ] ; then
 	if [ -f "$TOOLS" ] ; then
 		source "$TOOLS"
-		importcreds
+		importcreds "$CREDS"
 	else
 		APIUSER="administrator:administrator"
 	fi
diff --git a/tools_bin/ngcp-api-put b/tools_bin/ngcp-api-put
index c81f83aa69..81e238d259 100755
--- a/tools_bin/ngcp-api-put
+++ b/tools_bin/ngcp-api-put
@@ -20,7 +20,7 @@ EOF
 if [ -z "$APIUSER" ] ; then
   if [ -f "$TOOLS" ] ; then
     source "$TOOLS"
-    importcreds
+    importcreds "$CREDS"
   else
     APIUSER="administrator:administrator"
   fi