diff --git a/example_notebook.ipynb b/example_notebook.ipynb
index eae6005..5fad8d3 100644
--- a/example_notebook.ipynb
+++ b/example_notebook.ipynb
@@ -140,7 +140,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 12,
+   "execution_count": 2,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -150,7 +150,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 27,
+   "execution_count": 3,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -184,7 +184,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 21,
+   "execution_count": 4,
    "metadata": {},
    "outputs": [
     {
@@ -193,7 +193,7 @@
        "'Sfincs hydrodynamic model (C)'"
       ]
      },
-     "execution_count": 21,
+     "execution_count": 4,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -213,14 +213,14 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 28,
+   "execution_count": 5,
    "metadata": {},
    "outputs": [
     {
      "data": {
       "text/plain": []
      },
-     "execution_count": 28,
+     "execution_count": 5,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -231,7 +231,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 29,
+   "execution_count": 6,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -276,7 +276,9 @@
     {
      "data": {
       "text/plain": [
-       "{'get_input_var_names': ('zs', 'zb', 'qtsrc', 'zst_bnd'),\n",
+       "{'get_input_item_count': 4,\n",
+       " 'get_output_item_count': 6,\n",
+       " 'get_input_var_names': ('zs', 'zb', 'qtsrc', 'zst_bnd'),\n",
        " 'get_output_var_names': ('z_xz', 'z_yz', 'zs', 'zb', 'qtsrc', 'zst_bnd'),\n",
        " 'get_var_grid': 0,\n",
        " 'get_var_itemsize': 4,\n",
@@ -293,6 +295,8 @@
    "source": [
     "# Var methods\n",
     "{\n",
+    "    'get_input_item_count': model.get_input_item_count(),\n",
+    "    'get_output_item_count': model.get_output_item_count(),\n",
     "    'get_input_var_names': model.get_input_var_names(),\n",
     "    'get_output_var_names': model.get_output_var_names(),\n",
     "    'get_var_grid': model.get_var_grid('zs'),\n",
diff --git a/src/sfincs_bmi.cxx b/src/sfincs_bmi.cxx
index 1c20113..77eee86 100644
--- a/src/sfincs_bmi.cxx
+++ b/src/sfincs_bmi.cxx
@@ -73,12 +73,10 @@ std::string SfincsBmi::GetComponentName() {
   return "Sfincs hydrodynamic model (C)";
 }
 int SfincsBmi::GetInputItemCount() {
-  // TODO: implement
-  throw NotImplemented();
+  return this->GetInputVarNames().size();
 }
 int SfincsBmi::GetOutputItemCount() {
-  // TODO: implement
-  throw NotImplemented();
+  return this->GetOutputVarNames().size();
 }
 std::vector<std::string> SfincsBmi::GetInputVarNames() {
   // TODO: get from fortran