Extract dynamic entities

Is there any way to extract an entity without training. for example, if the user passes a message like want to know the status of {$train_name}

so in this case, whatever comes at {$train_name}, it will recognize it as train_name.

I think you could do this with duckling in your pipeline but that would only work if your entity fits into an existing duckling dimension or you can extend duckling with a dimension that fits your needs.

@stephens Thanks for your suggestion, but it’s not working.

Can you describe your entity and give examples?