Policies can be created independently of agents. E.g. see the random_policy in DQN tutorial

  
      

      colab.research.google.com
  

  
    

Google Colaboratory



  

  
    
    
  

  


If you are going to create your custom Agent  policy and collect_policy are constructor args:

  
      

      TensorFlow
  

  
    

tf_agents.agents.TFAgent  |  TensorFlow Agents 1

  Abstract base class for TF-based RL and Bandits agents.