diff --git a/src/RL/EnvHelper.jl b/src/RL/EnvHelper.jl
index 2e1f821..f0c47bb 100644
--- a/src/RL/EnvHelper.jl
+++ b/src/RL/EnvHelper.jl
@@ -20,12 +20,12 @@ struct EnvHelperSharedProps{H<:AbstractHook}
     function EnvHelperSharedProps(
         env::Env,
         agent::Agent,
-        hook::AbstractHook,
+        hook::H,
         n_steps_before_actions_update::Int64,
         goal_gyration_tensor_eigvals_ratio::Float64,
         n_particles::Int64,
-    )
-        return new(
+    ) where {H<:AbstractHook}
+        return new{H}(
             env,
             agent,
             hook,