Amazon Lex V2 Lambda python code to get intent name or any response back from lambda is not working

Question

''' Trying to get response back as name of the intent from lambda for Amazon Lex v2. It can be string or any response back in simple program.

I have referred the V2 Lex documentation but I can come-up with below code which shows error after several attempts. https://docs.aws.amazon.com/lexv2/latest/dg/lambda.html

error: "Invalid Lambda Response: Received error response from Lambda: Unhandled"

'''

def lambda_handler(event, context):
  entity = event["currentIntent"]["slots"]["Nm"].title()
  intent = event["currentIntent"]["name"]


  response = {
    'sessionState': {
        'dialogAction': {
            'type': 'Close'
        },
        'state': 'Fulfilled'
    },
    'messages': [
          'contentType': 'PlainText',
          'content': "The intent you are in now is "+intent+"!"
        ],
    
    }    

  return response

Answer 1

The 'messages' field is an array of objects, not an array of strings. It should be declared as follows:

'messages': [
          {
              'contentType': 'PlainText',
              'content': "The intent you are in now is "+intent+"!"
            }
        ]

---

Reference:

Amazon Lex - Lambda Response format

Answer 2

I faced the same issue. The solution that worked for me is like below

var response = {};
    response.messages = [
        message
    ];
    response.sessionState = {
        sessionAttributes:sessionAttributes,
        intent : {
            name : intentRequest.interpretations[0].intent.name,
            state : 'Fulfilled'
        },
        dialogAction: {   
            type: "Close",   
            fulfillmentState: "Fulfilled"
        }
    };

Refer to lex v2 developer guide page 69 Response format https://docs.aws.amazon.com/lexv2/latest/dg/lex2.0.pdf