问题
I made a chatbot in lex and for one particular intent, Lex is throwing the error,
An error has occurred: Invalid Bot Configuration: No usable messages
given the current slot and sessionAttribute set.
This error comes regardless of the input in case of that intent. I am not using any lambda functions at this point for this intent. Can someone guide me what this means? I am new to lex and I did not find references to what this error is about.
回答1:
Recently I got the same error with the test of my bot after saving some changes. After a while, finally, I found out that it was because my confirmation message was using some slots not defined at that point.
Example:
Let's assume we have:
- one required slot
{name} - one optional slot
{age} - and the confirmation message is
"Your name is {name} and your age is {age}, is that right?"
If Lex reaches the point to ask for the user confirmation and {age} was never assigned whether in any utterance or a lambda function, then Lex will return this error.
You must ensure that all slots used in messages are defined.
回答2:
I believe this error occurs because you have not configured Lex to have a response message set for that particular intent's CodeHook or Fulfillment.
If you are not using a Lambda Function for Fulfillment, be sure to select 'Return Parameters to Client' in the 'Fulfillment' section, then also supply a response message below that in 'Response' section.
Here's where to find that in the Lex Console:
回答3:
when I had the error it was because my response was attempting to use a slot that I had deleted {reward}, check your response to make sure you are not attempting to add an inactive slot. Also, Make sure your intent is set to the Latest version.
来源：https://stackoverflow.com/questions/48863158/error-no-usable-messages-given-the-current-slot-and-sessionattribute-set