Amazon Lex has got responses capability and SSML support in a text response

Amazon Lex Chatbot can now define a response from the AWS Management Console. The response will include messages chosen from a group of pre-defined messages which is generated by the developer. Messages in these messages groups can be a simple text or you can utilize a custom markup. You can also showcase a response card as part of the response message. This update will enhance and simplify the creation of dynamic conversation with Amazon Lex. You can also use the Speech Synthesis Markup Language in the text response.