"shared": false, // whether to shared networks for Actor-Critic
"hid_layers": [256, 128, 64],
"hid_layers_activation": "relu",
"out_layer_activation": null, // output layer activation
"init_fn": "xavier_uniform_", // weight initialization
"clip_grad_val": 1.0, // clip gradient by norm
"loss_spec": { // default loss function used for regression
"optim_spec": { // the optimizer and its arguments