diff --git a/nuplan/planning/script/config/simulation/observation/ml_planner_agents_observation.yaml b/nuplan/planning/script/config/simulation/observation/ml_planner_agents_observation.yaml
index eb6c5fabd6ca9a95f1ff295dd8e28bf13d147387..4db3ecdd821f4868a768627cc080976deebb28e8 100644
--- a/nuplan/planning/script/config/simulation/observation/ml_planner_agents_observation.yaml
+++ b/nuplan/planning/script/config/simulation/observation/ml_planner_agents_observation.yaml
@@ -7,6 +7,7 @@ occlusions: false  # Boolean to determine whether occlusions should be enabled
 planner_type: "ml"  # String to determine planner type (one of "ml", "idm", "pdm_closed", "pdm_hybrid")
 pdm_hybrid_ckpt: null  # Path to trained PDM hybrid model checkpoint
 
+# These defaults are taken from two_stage_controller.yaml
 tracker: 
   _target_: nuplan.planning.simulation.controller.tracker.lqr.LQRTracker
   _convert_: 'all'
diff --git a/nuplan/planning/simulation/observation/ml_planner_agents.py b/nuplan/planning/simulation/observation/ml_planner_agents.py
index b07f94f0039341c94081dd134fc398448f32c994..28570130310d64c753102424f5f56f267a621dbc 100644
--- a/nuplan/planning/simulation/observation/ml_planner_agents.py
+++ b/nuplan/planning/simulation/observation/ml_planner_agents.py
@@ -46,6 +46,8 @@ OPEN_LOOP_DETECTION_TYPES = [TrackedObjectType.PEDESTRIAN, TrackedObjectType.BIC
                              TrackedObjectType.CZONE_SIGN, TrackedObjectType.BARRIER, \
                              TrackedObjectType.TRAFFIC_CONE, TrackedObjectType.GENERIC_OBJECT]
 
+
+# Taken from idm_planner.yaml
 IDM_AGENT_CONFIG = {  
     "target_velocity": 10,             # Desired velocity in free traffic [m/s]
     "min_gap_to_lead_agent": 1.0,      # Minimum relative distance to lead vehicle [m]
@@ -57,7 +59,7 @@ IDM_AGENT_CONFIG = {
     "occupancy_map_radius": 40,        # The range around the ego to add objects to be considered [m]
 }
 
-
+# Taken from pdm_closed_planner.yaml in the TuPlan code
 PDM_CLOSED_AGENT_CONFIG = {  
     "trajectory_sampling": TrajectorySampling(num_poses=80, interval_length= 0.1),
     "proposal_sampling": TrajectorySampling(num_poses=40, interval_length= 0.1),
@@ -74,6 +76,7 @@ PDM_BATCH_IDM_CONFIG = {
     "decel_max":3.0
 }
 
+# Taken from pdm_hybrid_planner.yaml in the TuPlan code
 PDM_OFFSET_MODEL_CONFIG = {
     "trajectory_sampling": TrajectorySampling(num_poses=16, interval_length=0.5), 
     "history_sampling": TrajectorySampling(num_poses=10, interval_length=0.2),