> ## Documentation Index
> Fetch the complete documentation index at: https://docs.retellai.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Deprecating on 4/3/2026

* The following models are being deprecated and replaced with newer versions:
  * **OpenAI Realtime models:**
    * `gpt-4o-realtime` → replaced with `gpt-realtime-1.5`
    * `gpt-4o-mini-realtime` → replaced with `gpt-realtime-mini`
  * **Cartesia Sonic models:**
    * `sonic-2` → replaced with `sonic-3`
    * `sonic-turbo` → replaced with `sonic-3`
  * After 4/3/2026, the deprecated models will no longer be available.