Your agents now remember caller details, transfer calls based location and advanced conditions, reliably follow call flows, and filter out background voices for clearer conversations.

And now… GPT-5 is live in Synthflow!

Plus, you get new voice speed and volume controls, a GDPR toggle, and a direct Salesforce Service Cloud integration.

GPT-5 Now Live in Synthflow

OpenAI’s most advanced model yet is now available for your Synthflow Voice AI Agents. GPT-5 delivers stronger reasoning, richer context handling, and improved accuracy. What this means for you:

• Better reasoning: Handles more complex conversation paths with higher accuracy.

• Enterprise-ready: Built on our compliance foundation, with EU data residency in progress.

• Custom Evaluations: Measure GPT-5’s performance on real calls and adapt quickly.

Use GPT-5 inside Synthflow today to combine the latest model advances with the infrastructure that makes them production-ready. Try it on your own use-cases!

Persistent Memory for Voice Agents

Now your Voice Agents never forget a conversation. With Memory, your Voice Agents deliver personalized experiences across multiple conversations, so callers never have to repeat themselves.

• Continuous Context: Agents maintain conversation state across sessions, reducing caller frustration and improving customer satisfaction.

• User Metadata: Store and recall details for truly tailored interactions, making every call smarter and more efficient.

• Team Collaboration: With Memory Groups share memory states across your Voice Agents.

Turn on Memory today and let your Voice Agent build relationships with your users.

Salesforce Service Cloud Integration: Effortless Ticketing and CRM Sync (Enterprise)

Enterprise users can now connect directly to Salesforce Service Cloud with OAuth for seamless ticket creation, updates, and CRM integration.

• Automated Ticket Handling: Instantly create and update Cases, Leads, Contacts, and Opportunities in Salesforce during live calls.

• Enterprise-Grade Security: OAuth-based authentication ensures secure, compliant access for your team.

• Flexible CRM Support: Designed for Salesforce Service Cloud, with integrations on request with other platforms using OAuth including Zoho, Zendesk, and Intercom.

To enable, connect your account to Salesforce and then deploy via a Custom Action.

Voice Parameters for Speed, Volume, and Interruption Sensitivity

Your Voice Agents now sound even more natural and responsive. With new parameters for speed, volume, and interruption sensitivity you can fine-tune every call to fit your need.

• Voice Speed: Adjust how fast your agent speaks to match your audience and use case.

• Volume Control: Set the perfect loudness for accessibility and clarity, ensuring every caller feels heard.

• Interruption Sensitivity: Decide how easily your agent yields to human input, for conversations that feel truly human.

Try these new settings to create voice experiences that are as unique as your business. Available now via API and coming soon to the UI.

Learn more

Multi-Location Routing with Phone Book

Route calls dynamically based on user input, business hours, or custom logic. Replace dozens of manual transfer actions with a single, centralized phonebook.

• Bulk Management: Add, label, and organize up to 50 numbers per phonebook in the UI, with unlimited expansion via API.

• Conditional Routing: Route calls based on caller input, business hours, or custom logic.

• Easy Assignment: Attach phonebooks to agents instantly, so your team can scale without complexity.

Phonebook makes it easy for your Voice Agents to connect callers to the right location, no matter how many sites or departments you manage.

Learn more

Voice Isolation: Focused, Distraction-Free Calls

Our new Voice Isolation technology can now distinguish between the actual speaker and background voices, like TV or other people talking.

• True Speaker Recognition: Distinguishes the actual caller from background voices, eliminating confusion from TVs or other conversations in busy environments.

• Customizable Isolation Levels: Fine-tune how aggressively the agent filters out background voices, with settings from "basic" to "extreme" to fit your needs.

• Complete Upgrade, No Compromise: Includes all previous noise cancellation capabilities, with no performance loss. This is a full improvement, not a replacement.

To get started, simply enable Voice Isolation in your agent settings.

Structured Dialogue Engine: Predictable, Reliable Voice AI at Scale (Closed beta)

We’ve reimagined Flow Designer by upgrading with our new Structured Dialogue Engine (SDE) in the backend.  A foundational upgrade that solves the single biggest flaw of LLMs: unpredictability at scale. With SDE, building, launching, and maintaining advanced Voice AI Agents is no longer a fragile experiment: it’s a repeatable, dependable process.

Why? Because when you’re handling millions of business-critical calls, “winging it” doesn’t work.

What the Structured Dialogue Engine Brings:

• Reliability at Scale: By separating logic from language, SDE virtually eliminates hallucinations and rogue transitions.

• Maintainability: Modular flows let you adjust business logic without retraining models or rewriting prompts.

• Speed to Scale: Plug in new flows or integrations in minutes — no fragile mega-prompts to untangle.

• Trustworthy UX: Goal-oriented, structured dialogues drive user satisfaction and consistency.

• Compliance, Built In: Clear, auditable state-based flows make it easy to meet industry regulations.

Experience the next generation of conversation design and see how easy it is to launch agents that sound human and act with confidence.

Expanded Public API

Your have complete control over Voice Agent creation, updates, and configuration through our expanded public API.

• Agent Endpoints Fully Updated: All assistants endpoints got updated. You can now Get, Create, and Update all agent parameters.

• Fine-Grained Parameter Control: Parameters include allowed_idle_time_seconds (disconnect after idle period), background_noise (add natural ambient sounds), consent_message (custom recording consent). Control voice configuration, agent behavior, and call experience with 29 additional parameters.

• Language-Aware Synthesizer: Automatic voice synthesizer updates when changing language settings ensure your agents maintain optimal performance.

With full control over voice, behavior, and environment, this API update empowers you to craft agents as dynamic as your use case.

Learn more

Other Updates

Stay ahead with continuous improvements and new integrations designed to enhance your Voice AI operations.

• OpenAI Scale Tier for Enterprise: Enterprise customers now benefit by default from the OpenAI scale tier for enhanced performance and reliability. Learn more

• GDPR Data Retention Controls: Users can now enable a 30-day data retention limit, automatically deleting transcripts, caller IDs, and recordings for compliance.

• Enhanced Call Debugging: The get call API now returns additional fields to help users troubleshoot and optimize call performance.