Matrix/Features/Bring your own LLM
Which voice AI agent platforms have Bring your own LLM?
Use your own model or your own server as the agent's brain. Partial = choose from a provider list or enterprise-only key.
6 Yes2 Partial2 Unknown
Verified Yes: Vapi, Retell AI, ElevenLabs Agents, Deepgram Voice Agent API, LiveKit Agents, Vaani.
| Platform | Status | What the vendor says | Source |
|---|---|---|---|
| Deepgram Voice Agent APIDeepgram | Yes | BYO LLM "Bring your own LLM and voices"; discounted BYO tiers. | Source |
| ElevenLabs AgentsElevenLabs | Yes | Custom LLM Choose supported LLMs or connect your own model via server integration. | Source |
| LiveKit AgentsLiveKit | Yes | Any LLM plugin Plugins for any STT, LLM and TTS provider. | Source |
| Retell AIRetell AI | Yes | Custom LLM Connect your own LLM via WebSocket. | Source |
| VaaniVaani | Yes | BYOL Docs list Bring Your Own LLM. | Source |
| VapiVapi | Yes | Custom LLM server Point the agent at your own OpenAI-compatible LLM server. | Source |
| Cartesia AgentsCartesia | Partial | Pick from list / Line SDK Managed agents pick from Cartesia's model list; the Line SDK lets you connect any LLM in code. | Source |
| SynthflowSynthflow | Partial | OpenAI key (Enterprise) FAQ: no custom LLM; the only bring-your-own option is an OpenAI API key via BYOK on Enterprise. | Source |
| OpenAI Realtime APIOpenAI | No | Single model The model is the agent; you can't swap in another LLM. | Source |
| Bland AIBland | Unknown | Bland says it runs entirely on its own models; we found no documented way to bring your own LLM. | — |
| UltravoxUltravox | Unknown | Ultravox is its own speech-native model; no BYO LLM option found. | — |
Checked Nov 4, 2026. Filter the matrix by this feature →
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