A cluster of OpenAI API changes landed 9/8-9/10: GPT-Live 1 voice sessions (v1/live/sessions) went GA — full-duplex conversation that continues while a background model or agent reasons and calls tools, with Responses delegation or delegation to your own backend, priced at $0.05/minute billed by the second (backend model/tool usage billed separately). Prompt Cache Diagnostics went GA on Responses (GPT-5.6+): compares cache reuse between responses, identifies why misses happen, and produces troubleshooting guidance. Project API keys gained expiry dates with org- or project-level maximum-lifetime enforcement for admins. Two image models shipped (9/8): GPT Image 2.5 Sunburst for editing precision and Flare for fast everyday generation, both with xhigh/max quality settings on GPT Image 2 token rates.
OpenAI API wave: GPT-Live 1 GA, prompt-cache diagnostics GA, key lifecycles
OpenAI GPT-Live 1 provides full-duplex voice sessions that can delegate to a backend agent. On October 16, OpenAI opened text-described GPT-Live voice creation to all API customers and added nine German, French, Hindi, Japanese and Korean voices. Creation is free and speech uses GPT-Live billing; these voices do not work with TTS, Realtime or Chat Completions audio.
Imported from the existing research archive. Migration preserves the recorded judgment and is not a fresh verification.
What this means for you
For voice-agent teams, branded voices can now be tested without reference recordings. Organizations can save at most 100, voices are not guaranteed unique, and creation is incompatible with Zero Data Retention, so disclosure and retention requirements need review.
Evidence & related material
OpenAI made text-described GPT-Live voices available to all API customers.
Subsequent changes
Text-described GPT-Live voices reach GA for all API customers
Technical details & scores
| Gpt Live 1 | GA 2026-09-10; v1/live/sessions; full-duplex; continues while backend model/agent reasons and calls tools; Responses delegation or own backend; $0.05/min billed per second; backend usage billed separately |
|---|---|
| Prompt Cache Diagnostics | GA 2026-09-08; Responses API, GPT-5.6+; compares current vs previous response cache reuse, identifies miss causes, troubleshooting guidance |
| API Keys | 2026-09-10: project API key expiry dates; admin-enforced maximum key lifetime at org or project level |
| Gpt Image 2 5 | 2026-09-08: Sunburst (editing precision) + Flare (fast everyday); xhigh/max quality settings; GPT Image 2 token rates |
| Prompt To Voice | GA to all API customers; POST /v1/audio/voices; creation free; speech at GPT-Live rates; 100 saved voices per organization; GPT-Live only; creation incompatible with ZDR |