GPT-Realtime-1.5
GPT-Realtime-1.5 supports interactive voice agents with text, audio and image input. It returns text or speech and can call application tools.
The older session limits still matter
Its window is 32,000 tokens and its output limit is 4,096 tokens. Prompt caching is supported. Audio input and output use separate rates from text, so text-token prices alone do not describe the cost of a call.GPT-Realtime-1.5 official model documentation
Plan for a bounded conversation history
Practical guidance. For an existing phone assistant, inspect how long calls retain instructions and recent tool results within the session budget. Compare a newer model on the same call flow before migration. Preserve important confirmed facts when the application shortens conversation history.
Specifications & access
| Detail | Value and conditions |
|---|---|
| Access | API |
| Model identifiers | gpt-realtime-1.5 |
| Context window | 32,000 tokens Published model context; input and output share this budget GPT-Realtime-1.5 official model documentation |
| Maximum output | 4,096 tokens Published maximum output; bounded by the remaining context GPT-Realtime-1.5 official model documentation |
| Input and output | text, audio, image in; text, audio outGPT-Realtime-1.5 official model documentation |
| API routes | Realtime (v1/realtime)GPT-Realtime-1.5 official model documentation |
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