OpenAI Realtime_
>> Realtime is the right foundation when the model should hear and speak directly with low latency. We implement ephemeral credentials, WebRTC clients, SIP telephony bridges, tool/MCP wiring, and session policies so Realtime agents survive beyond a lab demo.
Calls/month
Production AI volume across live systems
PII detection
Compliance-ready detection accuracy in production AI
Projects
Shipped since 2012 with senior engineers only
Direct answer
Speech-to-speech only holds when WebRTC or SIP sessions, tools, and secrets are engineered for live calls. We ship OpenAI Realtime agents with production transports, in-session tools, and session policy that survives security review.
Trusted by leaders
>> System map
Adjacent AI layers we ship with this expertise. Technology-first, not vendor theater.
>> When this system fits
Honest fit gates. We will tell you when another approach is better.
Strong fit
- Browser or mobile voice agents that need WebRTC and barge-in
- Telephony agents on SIP with tool calling during the call
- Products that need speech-to-speech quality over chained STT/TTS pipelines
- Teams already on OpenAI who want Agents SDK RealtimeSession patterns
Weak fit
- Batch transcription or offline TTS with no live session requirement
- Projects that only need a hosted phone widget with no custom tools
- Teams unwilling to own session security, ephemeral keys, and evals
Stack: OpenAI Realtime · gpt-realtime · WebRTC · SIP · Agents SDK · MCP
What we deliver
_> Capabilities on this stack
WebRTC and SIP transports
Client Realtime over WebRTC; telephony via SIP; server WebSocket when you own the audio pipeline.
Tools and MCP in-session
Wire business tools and remote MCP servers into live audio sessions without freezing the conversation.
Session security
Ephemeral client secrets, scoped tools, and server-side policy so keys never ship in the browser bundle.
Prompt and voice tuning
Reusable prompts, turn-taking, preambles, and entity capture tuned against real call recordings.
Realtime delivery path
Transport and threat model
Choose WebRTC, SIP, or WebSocket. Lock credential flow and tool allow lists.
Live vertical slice
One conversation path with tools, transcripts, and latency metrics.
Production controls
Add handoff, evals, recording policy, and incident runbooks.
Related projects
_> See how we've applied our expertise
>>Related guides
_> Cite-worthy depth behind this stack
Frameworks and scorecards buyers and answer engines can quote. Each guide links back to delivery proof.
Vapi vs Retell vs OpenAI Realtime
Honest 2026 decision guide: Vapi for BYOK orchestration, Retell for turnkey telephony, OpenAI Realtime for speech-to-speech ownership.
Voice AI Latency, Barge-In, and Handoff
Production voice UX: first-audio latency, barge-in recovery, tool-blocked silence, and warm transfer that preserves context.
Inbound vs Outbound Voice AI Architecture
Design production inbound and outbound voice AI: queues, pacing, warm transfer, CRM sync, compliance, and latency budgets.
MCP Integration Guide: One Standard to Connect LLMs to Tools
A practical guide to Model Context Protocol: MCP servers, tools, permissions, security, environments, and contract tests to ship reliable LLM integrations.
FAQ
Yes. The Realtime API is generally available for production voice agents, including WebRTC clients and SIP telephony. We still treat latency, tools, and compliance as first-class engineering work.
When you need deterministic text control, existing text agents, or heavier reasoning that does not fit a live speech-to-speech loop. Many products mix both.
Yes. RealtimeSession with the right transport is the fastest path to tools, handoffs, and tracing around live audio.
>> Where this goes next
Adjacent expertise and the engagement models we deliver it through.