diff --git a/changes/ticket28011 b/changes/ticket28011
new file mode 100644
index 0000000000..5efc3c917b
--- /dev/null
+++ b/changes/ticket28011
@@ -0,0 +1,3 @@
+  o Code simplification and refactoring:
+    - Fix shellcheck warnings in run_calltool.sh. Resolves
+      ticket 28011.
diff --git a/scripts/maint/run_calltool.sh b/scripts/maint/run_calltool.sh
index efb8706fea..b0268322f4 100755
--- a/scripts/maint/run_calltool.sh
+++ b/scripts/maint/run_calltool.sh
@@ -15,10 +15,10 @@ SUBITEMS="fn_graph fn_invgraph fn_scc fn_scc_weaklinks module_graph module_invgr
 
 for calculation in $SUBITEMS; do
   echo "======== $calculation"
-  python -m calltool $calculation > callgraph/$calculation
+  python -m calltool "$calculation" > callgraph/"$calculation"
 done
 
-echo <<EOF > callgraph/README
+cat <<EOF > callgraph/README
 This directory holds output from calltool, as run on Tor.  For more
 information about each of these files, see the NOTES and README files in
 the calltool distribution.