I have set the AI and gotten a response from the AI, I saved that response as a variable {ai_response}. I have been trying to use an API POST to sent {ai_response} to a PHP script so it can count the characters in {ai_response}, divide that number by 4, and use that as an estimate to calculate how many tokens were used to generate the {ai_response}. I started down this path and then realized when I run an agent in Voiceflow that it tells me the number of tokens that are used with each AI input, output, and token_total. I am looking for the best way to dertermin how many total tokens are used and write that to a database so I can track customer data usage. Do you know if it is possible to access the total_tokens variable in Voiceflow? Or, is using an API to get an estimate of tokens used my best option. Sorry if I am asking a simple question, I am still learning, and thank you so much for any guidance you can give.