GPT-Realtime accepts and returns audio directly, while the Agents SDK supplies transport helpers plus tools, guardrails, handoffs, and session history.
Considerations
Not a turnkey contact center. Implement telephony operations, identity, tools, monitoring, evaluation, retention, and escalation.
Before you decide
Questions about Realtime API
How should I budget for Realtime API?
The published pricing signal is: GPT-Realtime audio $32 per million input audio tokens and $64 per million output audio tokens. The recorded pricing model is: Token-based API pricing for text, audio, and image modalities; audio input/output rates are published per million tokens. Ask the provider for a current quote covering the same workload, channels, subscriptions, usage and implementation costs.
Can Realtime API use my existing data?
The listed knowledge and data sources include Not publicly documented. Confirm permissions, freshness and failure behavior for your exact systems with the provider.
What should I test in a Realtime API pilot?
Run representative calls with the same instructions and escalation rules. Record voice quality, completed tasks, handoffs and total cost. Check these cautions: Not a turnkey contact center. Implement telephony operations, identity, tools, monitoring, evaluation, retention, and escalation.
Compare OpenAI Realtime with similar candidates
These products share recorded categories or company-size fit. Compare the actual channels, capabilities, and pricing before treating them as substitutes.
Programmable Voice component that connects a TwiML ConversationRelay session to an application WebSocket for STT/TTS, language settings, DTMF, and call events.
Telephony voice-agent runtime
Scope and signals
Best fit: Developers building their own voice-agent logic while keeping telephony, media handling, and call control in Twilio.
Voice stack: Cascaded speech interface with developer-supplied LLM
Test recognition, speech quality, interruptions, language switching, tool use, and human transfer with your own calls in the required language. Availability can vary by model, plan, and phone route.
DocsBot documents multilingual voice workflows and Japanese support. Verify the exact voice, phone path, and transfer behavior in your pilot. Review DocsBot language information ↗
Other providers’ language claims reflect cited vendor material; confirm Japanese and other required languages directly with each provider.
Listing does not imply endorsement or a performance guarantee. This directory is published by DocsBot. Editorial policy
Your business. Your shortlist.
Is Realtime API right for you?
Start with your website. Answer a few focused questions, then get a personalized PDF with fit, trade-offs, alternatives and a pilot plan for your call flow.
