diff --git a/larsim/PhotonPropagation/OpticalPropagation.fcl b/larsim/PhotonPropagation/OpticalPropagation.fcl
index 94c2a778f..64b198e44 100644
--- a/larsim/PhotonPropagation/OpticalPropagation.fcl
+++ b/larsim/PhotonPropagation/OpticalPropagation.fcl
@@ -3,25 +3,12 @@
 //---------------------------------------------------------------------------//
 #include "OpticalPropPDFastSimPAR_tool.fcl"
 
-process_name: OpticalPropagationProducer
+BEGIN_PROLOG
 
-services:
+OpticalPropagation:
 {
-    TimeTracker: {}
-    MemoryTracker: {}
+    module_type : OpticalPropagation
+    OpticalPropagationTool: @local::OpticalPropPDFastSimPAR
 }
 
-// Available tools are
-// @local::OpticalPropPDFastSimPAR : Semi-analytical model
-// @local::Celeritas               : Optical photon propagation on CPU and GPU
-// @local::Opticks                 : Optical photon propagation on Nvidia GPUs
-physics:
-{
-    producers:
-    {
-        OpticalPropagation:
-        {
-            OpticalPropagationTool: @local::OpticalPropPDFastSimPAR
-        }
-    }
-}
+END_PROLOG
diff --git a/larsim/PhotonPropagation/OpticalPropagationTools/CMakeLists.txt b/larsim/PhotonPropagation/OpticalPropagationTools/CMakeLists.txt
index 87afeeee3..f3ce027b9 100644
--- a/larsim/PhotonPropagation/OpticalPropagationTools/CMakeLists.txt
+++ b/larsim/PhotonPropagation/OpticalPropagationTools/CMakeLists.txt
@@ -1,10 +1,10 @@
-cet_make_library(LIBRARY_NAME OpticalPropagationTools INTERFACE
+cet_make_library(LIBRARY_NAME OpticalPropagationTool INTERFACE
   SOURCE IOpticalPropagation.h
   LIBRARIES INTERFACE
   lardataobj::Simulation
 )
 
-cet_write_plugin_builder(phot::OpticalPropagationTools art::tool Modules
+cet_write_plugin_builder(phot::OpticalPropagationTool art::tool Modules
   INSTALL_BUILDER
   LIBRARIES CONDITIONAL
   lardataobj::Simulation
@@ -13,9 +13,9 @@ cet_write_plugin_builder(phot::OpticalPropagationTools art::tool Modules
   nurandom::RandomUtils_NuRandomService_service
 )
 
-include(phot::OpticalPropagationTools)
+include(phot::OpticalPropagationTool)
 
-cet_build_plugin(OpticalPropPDFastSimPAR phot::OpticalPropagationTools
+cet_build_plugin(OpticalPropPDFastSimPAR phot::OpticalPropagationTool
   IMPL_SOURCE OpticalPropPDFastSimPAR.cc
   LIBRARIES PRIVATE
   larsim::PhotonPropagation
diff --git a/larsim/PhotonPropagation/OpticalPropagationTools/OpticalPropPDFastSimPAR_tool.fcl b/larsim/PhotonPropagation/OpticalPropagationTools/OpticalPropPDFastSimPAR_tool.fcl
index 4bc1defed..a8102e1d8 100644
--- a/larsim/PhotonPropagation/OpticalPropagationTools/OpticalPropPDFastSimPAR_tool.fcl
+++ b/larsim/PhotonPropagation/OpticalPropagationTools/OpticalPropPDFastSimPAR_tool.fcl
@@ -27,9 +27,9 @@ OpticalPropPDFastSimPAR:
     VUVTiming:               @local::common_vuv_timing_parameterization
 
     // Required detector-specific parameters:
-    VISTiming:
-    VUVHits:
-    VISHits:
+    // VISTiming:
+    // VUVHits:
+    // VISHits:
 }
 
 END_PROLOG
diff --git a/larsim/PhotonPropagation/OpticalPropagation_job.fcl b/larsim/PhotonPropagation/OpticalPropagation_job.fcl
new file mode 100644
index 000000000..e7b1568e5
--- /dev/null
+++ b/larsim/PhotonPropagation/OpticalPropagation_job.fcl
@@ -0,0 +1,25 @@
+//---------------------------------------------------------------------------//
+// Job execution file for the OpticalPropagation module
+//---------------------------------------------------------------------------//
+#include "OpticalPropPDFastSimPAR_tool.fcl"
+
+process_name: opticalpropagation
+
+services:
+{
+    TimeTracker: {}
+    MemoryTracker: {}
+}
+
+physics:
+{
+    producers:
+    {
+        OpticalPropagation:
+        {
+            OpticalPropagationTool: @local::OpticalPropPDFastSimPAR
+        }
+    }
+
+    end_path: [ OpticalPropagation ]
+}
diff --git a/larsim/PhotonPropagation/OpticalPropagation_module.cc b/larsim/PhotonPropagation/OpticalPropagation_module.cc
index 4282c823b..70b35db6a 100644
--- a/larsim/PhotonPropagation/OpticalPropagation_module.cc
+++ b/larsim/PhotonPropagation/OpticalPropagation_module.cc
@@ -19,6 +19,7 @@
 #include "art/Framework/Principal/Handle.h"
 #include "art/Utilities/make_tool.h"
 #include "fhiclcpp/ParameterSet.h"
+#include "fhiclcpp/types/DelegatedParameter.h"
 #include "messagefacility/MessageLogger/MessageLogger.h"
 
 #include "larsim/PhotonPropagation/OpticalPropagationTools/IOpticalPropagation.h"
@@ -33,8 +34,9 @@ class phot::OpticalPropagation : public art::EDProducer {
 public:
   //! FHiCL configuration parameter
   struct Config {
-    fhicl::Table<fhicl::ParameterSet> OpticalPropagationTools{
-      fhicl::Name("OpticalPropagationTools")};
+    fhicl::DelegatedParameter OpticalPropagationTool{
+      fhicl::Name("OpticalPropagationTool"),
+      fhicl::Comment("Tool configuration block with tool_type and parameters")};
   };
 
   //!@{
@@ -75,8 +77,9 @@ phot::OpticalPropagation::OpticalPropagation(Parameters const& config) : EDProdu
 {
   using IOP = phot::IOpticalPropagation;
 
+  auto const& ps = config().OpticalPropagationTool.get<fhicl::ParameterSet>();
   fOpticalPropagationTool =
-    std::unique_ptr<IOP>(art::make_tool<IOP>(config().OpticalPropagationTools()));
+    std::unique_ptr<phot::IOpticalPropagation>(art::make_tool<phot::IOpticalPropagation>(ps));
 
   fOpticalPropagationTool->InitializeTools(
     art::ServiceHandle<rndm::NuRandomService>()->registerAndSeedEngine(