Text to Speech Eleven v3 (alpha): Released Eleven v3 (alpha), our most expressive Text to Speech model, as a research preview. Agents Platform Custom voice settings in multi-voice: Added support for configuring individual voice settings per supported voice in multi-voice agents, allowing fine-tuned control over stability, speed, similarity boost, and streaming latency for each voice.Silent transfer to human in Twilio: Added backend configuration support for silent (cold) transfer to number in the Twilio native integration, enabling seamless handoff without announcing the transfer to callers.Batch calling retry and cancel: Added support for retrying outbound calls to phone numbers that did not respond during a batch call, along with the ability to cancel ongoing batch operations for better campaign management.LLM pinning: Added support for versioned LLM models with explicit checkpoint identifiersCustom LLM headers: Added support for passing custom headers to custom LLMsFixed issue in non-latin languages: Fixed an issue causing some conversations in non latin alphabet languages to fail. SDKs Python SDK v2.3.0: Released Python SDK v2.3.0JavaScript SDK v2.2.0: Released JavaScript SDK v2.2.0 API
Fetched April 9, 2026