curl --request POST \
  --url https://api.helicone.ai/v1/public/dataisbeautiful/ttft-vs-prompt-length \
  --header 'Content-Type: application/json' \
  --header 'authorization: <api-key>' \
  --data '{
  "provider": "OPENAI",
  "models": [
    "gpt-3.5"
  ],
  "timespan": "7d"
}'

{
  "data": [
    {
      "prompt_length": 123,
      "ttft_normalized_p75": 123,
      "ttft_normalized_p99": 123,
      "ttft_normalized": 123,
      "ttft_p75": 123,
      "ttft_p99": 123,
      "ttft": 123
    }
  ]
}