diff --git a/check-linuxcnc-wasm-shims-source-map.sh b/check-linuxcnc-wasm-shims-source-map.sh
index 93b1a4e..1154969 100755
--- a/check-linuxcnc-wasm-shims-source-map.sh
+++ b/check-linuxcnc-wasm-shims-source-map.sh
@@ -49,8 +49,17 @@ grep -F 'RCS_STAT_MSG::RCS_STAT_MSG' "$linuxcnc_root/src/libnml/nml/stat_msg.cc"
 grep -F 'print_rcs_error_new' "$linuxcnc_root/src/libnml/rcs/rcs_print.cc" >/dev/null
 grep -F 'rtapi_snprintf' "$linuxcnc_root/src/rtapi/uspace_common.h" >/dev/null
 grep -F 'class PythonPlugin' "$linuxcnc_root/src/emc/pythonplugin/python_plugin.hh" >/dev/null
+grep -F 'PLUGIN_PYTHON_NOT_INITIALIZED = -12,' "$linuxcnc_root/src/emc/pythonplugin/python_plugin.hh" >/dev/null
+grep -F 'PLUGIN_NO_CALLABLE = 1,' "$linuxcnc_root/src/emc/pythonplugin/python_plugin.hh" >/dev/null
+grep -F 'PLUGIN_EXCEPTION = 2' "$linuxcnc_root/src/emc/pythonplugin/python_plugin.hh" >/dev/null
 grep -F 'PythonPlugin::instantiate' "$linuxcnc_root/src/emc/pythonplugin/python_plugin.cc" >/dev/null
 grep -F 'if (status < PLUGIN_OK)' "$linuxcnc_root/src/emc/pythonplugin/python_plugin.cc" >/dev/null
+grep -F 'retval = bp::exec_file(cmd, main_namespace, main_namespace);' \
+    "$linuxcnc_root/src/emc/pythonplugin/python_plugin.cc" >/dev/null
+grep -F 'retval = bp::exec(cmd, main_namespace, main_namespace);' \
+    "$linuxcnc_root/src/emc/pythonplugin/python_plugin.cc" >/dev/null
+grep -F 'PyObject *rv = PyObject_Call(function.ptr(), tupleargs.ptr(), kwargs.ptr());' \
+    "$linuxcnc_root/src/emc/pythonplugin/python_plugin.cc" >/dev/null
 grep -F '#define TOOL_MMAP_FILENAME ".tool.mmap"' "$linuxcnc_root/src/emc/tooldata/tooldata_mmap.cc" >/dev/null
 grep -F 'int tool_nml_register(CANON_TOOL_TABLE *tblptr)' "$linuxcnc_root/src/emc/tooldata/tooldata_nml.cc" >/dev/null
 grep -F 'int tooldata_db_init(char progname_plus_args[]' "$linuxcnc_root/src/emc/tooldata/tooldata_db.cc" >/dev/null
@@ -153,6 +162,45 @@ for needle in [
     if needle not in runtime_probe:
         raise SystemExit(f"runtime probe missing HAL unavailable assertion: {needle}")
 
+python_plugin_shim = Path("core/wasm_shims/pythonplugin/python_plugin.cc").read_text(encoding="utf-8")
+python_plugin_probe = Path("core/wasm_shims/pythonplugin/python_plugin_probe_main.cc").read_text(encoding="utf-8")
+python_c_api_shim = Path("core/wasm_shims/python_c_api_shim.cc").read_text(encoding="utf-8")
+for forbidden in [
+    "bp::exec(",
+    "bp::exec_file(",
+    "PyObject_Call(",
+]:
+    if forbidden in python_plugin_shim:
+        raise SystemExit(f"PythonPlugin wasm shim must not execute Python: {forbidden}")
+for needle in [
+    "python disabled in wasm-safe probe",
+    "status = PLUGIN_PYTHON_NOT_INITIALIZED;",
+    "return PLUGIN_NO_CALLABLE;",
+    "status = PLUGIN_EXCEPTION;",
+    "if (status < PLUGIN_OK)",
+]:
+    if needle not in python_plugin_shim:
+        raise SystemExit(f"PythonPlugin wasm shim missing disabled-python boundary: {needle}")
+for needle in [
+    "PLUGIN_NO_SECTION",
+    "PLUGIN_BAD_INIFILE",
+    "PLUGIN_PYTHON_NOT_INITIALIZED",
+    "PLUGIN_NO_CALLABLE",
+    "PLUGIN_EXCEPTION",
+    "handle_pyerror().empty()",
+]:
+    if needle not in python_plugin_probe:
+        raise SystemExit(f"PythonPlugin probe missing disabled-python status assertion: {needle}")
+for needle in [
+    "Py_IsInitialized",
+    "PyObject_CallMethod",
+    "Py_BuildValue",
+    "PyModule_Create",
+    "PyType_Ready",
+]:
+    if needle not in python_c_api_shim:
+        raise SystemExit(f"Python C API shim missing symbol boundary: {needle}")
+
 for phrase in [
     "must not add CNC behavior",
     "must not expand the temporary smoke parser",
@@ -164,6 +212,9 @@ for phrase in [
     "must leave HAL values unavailable",
     "must not switch browser-safe probes into task mode",
     "must not become a shell expansion feature",
+    "must not become Python execution",
+    "keeping Python execution disabled",
+    "must not execute `bp::exec`, `bp::exec_file`, or",
     "inactive-DB return values",
     "negative-status short-circuit behavior",
     "./check-linuxcnc-wasm-shims-source-map.sh",
diff --git a/docs/linuxcnc-wasm-shims-source-map.md b/docs/linuxcnc-wasm-shims-source-map.md
index a7e4b56..dc74061 100644
--- a/docs/linuxcnc-wasm-shims-source-map.md
+++ b/docs/linuxcnc-wasm-shims-source-map.md
@@ -38,6 +38,18 @@ only; it must not add CNC behavior and must not expand the temporary smoke parse
 - `wordexp()` support is limited to the browser-safe path expansion needed by
   `src/emc/rs274ngc/rs274ngc_pre.cc`; it must not become a shell expansion feature.
 
+## Python Shim Boundaries
+
+- `core/wasm_shims/python_c_api_shim.cc` satisfies Python C API symbols used by
+  LinuxCNC RS274/remap sources; it must not become Python execution.
+- `core/wasm_shims/pythonplugin/python_plugin.cc` must preserve LinuxCNC
+  `PythonPlugin` status edges for `PLUGIN_NO_SECTION`, `PLUGIN_BAD_INIFILE`,
+  `PLUGIN_PYTHON_NOT_INITIALIZED`, `PLUGIN_NO_CALLABLE`, and
+  `PLUGIN_EXCEPTION` while keeping Python execution disabled.
+- The PythonPlugin shim must not execute `bp::exec`, `bp::exec_file`, or
+  `PyObject_Call`; those remain browser blockers until implemented as a
+  source-backed browser-safe LinuxCNC adaptation.
+
 ## Boundaries
 
 - The CMake `linuxcnc_wasm_safe_probe_shims` set and `list-linuxcnc-wasm-safe-shims.sh` must stay synchronized.