diff --git a/R/SimulationObjectClass.R b/R/SimulationObjectClass.R
index 6813fda..22ca9d0 100644
--- a/R/SimulationObjectClass.R
+++ b/R/SimulationObjectClass.R
@@ -8,6 +8,7 @@ setClass("SimulationObject",
            effort = "ANY",
            detect = "ANY",
            report = "ANY",
+           metadata = "ANY",
            hash = "ANY"
          )
 )
@@ -22,6 +23,7 @@ SimulationObject <- function(background, state_env = NULL, state_target_suitabil
       effort = effort,
       detect = detect,
       report = report,
+      metadata = list(),
       hash = NULL)
 
   new("SimulationObject",
@@ -32,6 +34,7 @@ SimulationObject <- function(background, state_env = NULL, state_target_suitabil
       effort = effort,
       detect = detect,
       report = report,
+      metadata = list(),
       hash = hash_sim_obj(tmp)
   )
 }
diff --git a/R/sim_detect.R b/R/sim_detect.R
index 1dcec4d..9a2b687 100644
--- a/R/sim_detect.R
+++ b/R/sim_detect.R
@@ -23,6 +23,8 @@ sim_detect <- function(simulation_object, fun, ...) {
   detections <- fun(simulation_object, ...)
 
   # validity checks
+  fun_args <- as.list(match.call())
+  simulation_object_original@metadata[["detect"]] <- fun_args[3:length(fun_args)]
 
   simulation_object_original@detect <- detections
   simulation_object_original@hash <- hash_sim_obj(simulation_object_original)
diff --git a/R/sim_effort.R b/R/sim_effort.R
index b7e177e..8a2b596 100644
--- a/R/sim_effort.R
+++ b/R/sim_effort.R
@@ -23,6 +23,8 @@ sim_effort <- function(simulation_object, fun, ...) {
   effort <- fun(simulation_object, ...)
 
   # validity checks
+  fun_args <- as.list(match.call())
+  simulation_object_original@metadata[["effort"]] <- fun_args[3:length(fun_args)]
 
   simulation_object_original@effort <- effort
   simulation_object_original@hash <- hash_sim_obj(simulation_object_original)
diff --git a/R/sim_report.R b/R/sim_report.R
index 209ef4b..f3ccef7 100644
--- a/R/sim_report.R
+++ b/R/sim_report.R
@@ -23,6 +23,8 @@ sim_report <- function(simulation_object, fun, ...) {
   report <- fun(simulation_object, ...)
 
   # validity checks
+  fun_args <- as.list(match.call())
+  simulation_object_original@metadata[["report"]] <- fun_args[3:length(fun_args)]
 
   simulation_object_original@report <- report
   simulation_object_original@hash <- hash_sim_obj(simulation_object_original)
diff --git a/R/sim_state_env.R b/R/sim_state_env.R
index 1bddbe1..e61c8c2 100644
--- a/R/sim_state_env.R
+++ b/R/sim_state_env.R
@@ -55,6 +55,10 @@ sim_state_env <- function(simulation_object, fun= NULL, filename = NULL, spatras
   #create hash, having set the hash to NULL
   simulation_object_original@hash <- hash_sim_obj(simulation_object_original)
 
+  #set metadata
+  fun_args <- as.list(match.call())
+  simulation_object_original@metadata[["state_env"]] <- fun_args[3:length(fun_args)]
+
   # Return the updated simulation_object
   return(simulation_object_original)
 }
diff --git a/R/sim_state_target_realise.R b/R/sim_state_target_realise.R
index 9dbe185..e068470 100644
--- a/R/sim_state_target_realise.R
+++ b/R/sim_state_target_realise.R
@@ -28,6 +28,9 @@ sim_state_target_realise <- function(simulation_object,fun, filename=NULL, ...)
     realised <- write_raster_return_filename(realised,filename)
   }
 
+  fun_args <- as.list(match.call())
+  simulation_object_original@metadata[["state_target_realised"]] <- fun_args[3:length(fun_args)]
+
   simulation_object_original@state_target_realised <- realised
   simulation_object_original@hash <- hash_sim_obj(simulation_object_original)
   simulation_object_original
diff --git a/R/sim_state_target_suitability.R b/R/sim_state_target_suitability.R
index e635694..e5d4a47 100644
--- a/R/sim_state_target_suitability.R
+++ b/R/sim_state_target_suitability.R
@@ -28,6 +28,9 @@ sim_state_target_suitability <- function(simulation_object,fun,filename = NULL,
     suitability <- write_raster_return_filename(suitability,filename)
   }
 
+  fun_args <- as.list(match.call())
+  simulation_object_original@metadata[["state_target_suitability"]] <- fun_args[3:length(fun_args)]
+
   simulation_object_original@state_target_suitability <- suitability
   simulation_object_original@hash <- hash_sim_obj(simulation_object_original)
   simulation_object_original