diff --git a/python/openmmtorch.i b/python/openmmtorch.i
index 05988e3..558ce0f 100644
--- a/python/openmmtorch.i
+++ b/python/openmmtorch.i
@@ -69,11 +69,14 @@ public:
     void setOutputsForces(bool);
     bool getOutputsForces() const;
     int getNumGlobalParameters() const;
+    int getNumEnergyParameterDerivatives() const;
     int addGlobalParameter(const std::string& name, double defaultValue);
     const std::string& getGlobalParameterName(int index) const;
     void setGlobalParameterName(int index, const std::string& name);
     double getGlobalParameterDefaultValue(int index) const;
     void setGlobalParameterDefaultValue(int index, double defaultValue);
+    void addEnergyParameterDerivative(const std::string& name);
+    const std::string& getEnergyParameterDerivativeName(int index) const;
     void setProperty(const std::string& name, const std::string& value);
     const std::map<std::string, std::string>& getProperties() const;