diff --git a/core/wasm_shims/boost/python/dict.hpp b/core/wasm_shims/boost/python/dict.hpp
index db5b5b5..15a1051 100644
--- a/core/wasm_shims/boost/python/dict.hpp
+++ b/core/wasm_shims/boost/python/dict.hpp
@@ -1,4 +1,5 @@
 #pragma once
 
+// LinuxCNC source basis: interp_o_word.cc, interp_namedparams.cc, and
+// rs274ngc_pre.cc use boost::python::dict for Python call kwargs.
 #include "boost/python/object.hpp"
-
diff --git a/core/wasm_shims/boost/python/extract.hpp b/core/wasm_shims/boost/python/extract.hpp
index db5b5b5..5e3d27d 100644
--- a/core/wasm_shims/boost/python/extract.hpp
+++ b/core/wasm_shims/boost/python/extract.hpp
@@ -1,4 +1,5 @@
 #pragma once
 
+// LinuxCNC source basis: interp_python.cc, interp_namedparams.cc,
+// rs274ngc_pre.cc, and python_plugin.cc use boost::python::extract.
 #include "boost/python/object.hpp"
-
diff --git a/core/wasm_shims/boost/python/import.hpp b/core/wasm_shims/boost/python/import.hpp
index db5b5b5..9f153f4 100644
--- a/core/wasm_shims/boost/python/import.hpp
+++ b/core/wasm_shims/boost/python/import.hpp
@@ -1,4 +1,5 @@
 #pragma once
 
+// LinuxCNC source basis: interp_python.cc, rs274ngc_pre.cc, and
+// python_plugin.cc use boost::python::import.
 #include "boost/python/object.hpp"
-
diff --git a/core/wasm_shims/boost/python/list.hpp b/core/wasm_shims/boost/python/list.hpp
index db5b5b5..09dd458 100644
--- a/core/wasm_shims/boost/python/list.hpp
+++ b/core/wasm_shims/boost/python/list.hpp
@@ -1,4 +1,5 @@
 #pragma once
 
+// LinuxCNC source basis: interp_o_word.cc, interp_namedparams.cc, and
+// rs274ngc_pre.cc use boost::python::list while preparing Python call args.
 #include "boost/python/object.hpp"
-
diff --git a/core/wasm_shims/boost/python/scope.hpp b/core/wasm_shims/boost/python/scope.hpp
index db5b5b5..ae45589 100644
--- a/core/wasm_shims/boost/python/scope.hpp
+++ b/core/wasm_shims/boost/python/scope.hpp
@@ -1,4 +1,5 @@
 #pragma once
 
+// LinuxCNC source basis: rs274ngc_pre.cc uses boost::python::scope to publish
+// interpreter.this for Python/remap handlers.
 #include "boost/python/object.hpp"
-
diff --git a/core/wasm_shims/boost/python/str.hpp b/core/wasm_shims/boost/python/str.hpp
index a330665..0369316 100644
--- a/core/wasm_shims/boost/python/str.hpp
+++ b/core/wasm_shims/boost/python/str.hpp
@@ -1,3 +1,5 @@
 #pragma once
 
+// LinuxCNC source basis: interp_python.cc and python_plugin.cc use
+// boost::python::str while formatting Python exceptions.
 #include "boost/python/object.hpp"
diff --git a/core/wasm_shims/boost/python/tuple.hpp b/core/wasm_shims/boost/python/tuple.hpp
index a330665..b4a7399 100644
--- a/core/wasm_shims/boost/python/tuple.hpp
+++ b/core/wasm_shims/boost/python/tuple.hpp
@@ -1,3 +1,5 @@
 #pragma once
 
+// LinuxCNC source basis: interp_o_word.cc, interp_namedparams.cc, and
+// rs274ngc_pre.cc use boost::python::tuple for Python call arguments.
 #include "boost/python/object.hpp"
diff --git a/test-linuxcnc-wasm-cmake-safe-probe.sh b/test-linuxcnc-wasm-cmake-safe-probe.sh
index 88cfd7e..4cff6f4 100755
--- a/test-linuxcnc-wasm-cmake-safe-probe.sh
+++ b/test-linuxcnc-wasm-cmake-safe-probe.sh
@@ -1413,6 +1413,13 @@ grep -F 'LinuxCNC source basis: src/emc/rs274ngc/interp_base.hh derives InterpBa
 grep -F 'class noncopyable' core/wasm_shims/boost/noncopyable.hpp >/dev/null
 grep -F 'noncopyable(const noncopyable &) = delete;' core/wasm_shims/boost/noncopyable.hpp >/dev/null
 grep -F 'LinuxCNC source basis: src/emc/rs274ngc/interp_python.cc,' core/wasm_shims/boost/python/object.hpp >/dev/null
+grep -F 'LinuxCNC source basis: interp_o_word.cc, interp_namedparams.cc, and' core/wasm_shims/boost/python/list.hpp >/dev/null
+grep -F 'LinuxCNC source basis: interp_o_word.cc, interp_namedparams.cc, and' core/wasm_shims/boost/python/dict.hpp >/dev/null
+grep -F 'LinuxCNC source basis: interp_o_word.cc, interp_namedparams.cc, and' core/wasm_shims/boost/python/tuple.hpp >/dev/null
+grep -F 'LinuxCNC source basis: interp_python.cc, interp_namedparams.cc,' core/wasm_shims/boost/python/extract.hpp >/dev/null
+grep -F 'LinuxCNC source basis: interp_python.cc, rs274ngc_pre.cc, and' core/wasm_shims/boost/python/import.hpp >/dev/null
+grep -F 'LinuxCNC source basis: interp_python.cc and python_plugin.cc use' core/wasm_shims/boost/python/str.hpp >/dev/null
+grep -F 'LinuxCNC source basis: rs274ngc_pre.cc uses boost::python::scope' core/wasm_shims/boost/python/scope.hpp >/dev/null
 test -f core/wasm_shims/libgen.h
 grep -F 'LinuxCNC source basis: src/emc/rs274ngc/interp_o_word.cc uses basename()' core/wasm_shims/libgen.h >/dev/null
 grep -F 'inline char *basename(const char *path)' core/wasm_shims/libgen.h >/dev/null