GPT-5.2 integration in Telnyx VoiceAI Assistant

11, Dec 2025

Telnyx VoiceAI Assistants now support OpenAI’s GPT-5.2 model, giving developers access to the latest generation of frontier LLM capabilities for real-time telephony-centric voice applications.

This integration enhances intelligence and flexibility in multi-turn conversational workflows while addressing real-world performance needs.

What’s new

  • GPT-5.2 model support: Select GPT-5.2 in the AI Assistant model picker or via API.
  • Extended context: Bigger context handling for more complex dialogs and history.
  • Fallback routing: Developers can configure automated model mode switches based on task complexity.
  • Unified billing: Usage of GPT-5.2 through Telnyx bills at consistent pricing without separate API billing.

Why it matters

  • Improves reasoning and long-context understanding for multi-turn conversations.
  • Offers configurable performance profiles so teams can optimize for latency or depth.
  • Reduces retries and custom prompt logic in pipeline workflows.
  • Enables handling large task contexts (documents, histories) without fragmenting user state.

Example use cases

  • Contact center assistants that require consistent handling of multi-step support flows.
  • Enterprise knowledge bots that use extended context for policies, contracts, or manuals.
  • Interactive IVRs that combine natural language with backend system lookups.

Getting started

gpt 5.2.gif

  1. Open the Mission Control Portal and go to AI Assistants.
  2. Edit or create an Assistant and choose GPT-5.2 in the model configuration.
  3. Optionally choose Instant, Thinking, or Pro to tailor latency vs. reasoning effort.
  4. Test end-to-end dialogs in the Assistant Builder before deploying.
  5. Monitor interaction latency and intent accuracy via Conversation History.

Log in to the Mission Control Portal, navigate to AI Assistants, and set the maximum assistant duration as required.