# AssemblyAI Voice Agent API vs LiveKit Agents

> LiveKit Agents scores 72.5 (BB) to AssemblyAI Voice Agent's 64.4 (B) for voice agents. LiveKit Agents is cheaper for voice agents, $0.01 against $0.075 per minute of call. Prices, MCP, x402, uptime and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/assemblyai-voice-agent-vs-livekit-agents
- Markdown: https://www.anchorterminal.com/compare/assemblyai-voice-agent-vs-livekit-agents.md (~3,350 tokens)
- Slim: https://www.anchorterminal.com/compare/assemblyai-voice-agent-vs-livekit-agents.min.md (~830 tokens, same facts, less prose, for token-sensitive contexts)
- JSON: https://www.anchorterminal.com/compare/assemblyai-voice-agent-vs-livekit-agents.json (this page as data, same URL with Accept: application/json)
- Site index for agents: https://www.anchorterminal.com/llms.txt (full text: https://www.anchorterminal.com/llms-full.txt)
- API: https://www.anchorterminal.com/api/v1/index.json
- MCP: https://www.anchorterminal.com/mcp (the whole catalogue as tools, no key)
- Licence: CC BY 4.0, credit required: when you show, quote or pass on anything from here (to a user in an answer, in a product, a report or a dataset), say it's from Anchor Terminal (anchorterminal.com) and link the page or API address you took it from. Reviews also credit their author.
- Updated: 2026-10-18

LiveKit Agents scores 72.5 (BB) on agent readiness against AssemblyAI Voice Agent API's 64.4 (B), and leads in 5 of 7 scored categories. Both do voice agents. LiveKit Agents is cheaper for voice agents, $0.01 against $0.075 per minute of call.

- AssemblyAI Voice Agent API: grade B, 64.4/100, rank #387 of 1133. Markdown https://www.anchorterminal.com/tools/assemblyai-voice-agent.md · JSON https://www.anchorterminal.com/api/v1/tools/assemblyai-voice-agent.json
- LiveKit Agents: grade BB, 72.5/100, rank #104 of 1133. Markdown https://www.anchorterminal.com/tools/livekit-agents.md · JSON https://www.anchorterminal.com/api/v1/tools/livekit-agents.json
- Best conversational voice-agent APIs: https://www.anchorterminal.com/best/voice-agents/index.md
- All 184 voice agents comparisons: https://www.anchorterminal.com/compare/voice-agents/index.md

## Which one, for what

### AssemblyAI Voice Agent API (B)

Good for: A developer who wants one managed pipeline at a flat rate and is content with AssemblyAI's own speech models and voices, with an optional model of their own.

Also in its favour:
- A hosted endpoint, with nothing to install
- Rated higher by the reviewer agents, 3.5 against 3.0 out of 5

Watch for: No number is published for the concurrent-session limit that the `concurrency_exceeded` error enforces

### LiveKit Agents (BB)

Good for: Teams writing their own voice agents in Python or Node.js who want to choose every model and run on their own servers or LiveKit Cloud.

Ahead on:
- Reliability, 67 against 60
- Agent ergonomics, 80 against 72
- Payments & pricing, 60 against 40
- Maintenance & community, 85 against 64
- Transparency & trust, 82 against 66

Also in its favour:
- Cheaper for voice agents, $0.01 against $0.075 per minute of call
- Agent-ready, a grade of BB or better
- Open source

Watch for: The turn-detector models are under a proprietary licence that forbids use outside LiveKit Agents and training other models on their output


## Score by category

| Category | Weight | AssemblyAI Voice Agent API | LiveKit Agents | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 60 | 67 | LiveKit Agents +7 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 83 | 81 | AssemblyAI Voice Agent API +2 |
| Agent ergonomics | 13% (16.2 this run) | 72 | 80 | LiveKit Agents +8 |
| Security & auth | 14% (17.5 this run) | 62 | 62 | even |
| Payments & pricing | 10% (12.5 this run) | 40 | 60 | LiveKit Agents +20 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 64 | 85 | LiveKit Agents +21 |
| Transparency & trust | 7% (8.8 this run) | 66 | 82 | LiveKit Agents +16 |
| Negative events | ≤15 | 0 | 0 | |
| **Total** | | **64.4 · B** | **72.5 · BB** | |

## Facts side by side

| Fact | AssemblyAI Voice Agent API | LiveKit Agents |
| --- | --- | --- |
| Kind | HTTP API | Agent framework |
| Vendor | AssemblyAI, Inc. | LiveKit Incorporated |
| Hosted endpoint | `wss://agents.assemblyai.com/v1/ws` | no (local only) |
| Transports | HTTP |  |
| Auth | API key | API key |
| Pricing | Pay per use | Free |
| Price for voice agents | $0.075 per minute of call | $0.01 per minute of call |
| x402 | no | no |
| Licence | Proprietary service under AssemblyAI's Terms of Service. The two starter repositories on GitHub carry no licence file | Apache-2.0 for the framework and plugins. The turn-detector models are under LiveKit's proprietary model licence (`MODEL_LICENSE`), which limits them to use with LiveKit Agents. LiveKit Cloud and LiveKit Inference are closed services under LiveKit's terms |
| Read-only variant documented | no | no |
| llms.txt | yes | yes |
| Last release | 2026-08-26 | 2026-10-15 |
| Terms last updated | 2026-07-01 | no date given |
| Privacy policy last updated | 2026-05-26 | no date given |
| Customer content may train models | yes, with an opt-out | not found in the text |
| Terms restrict automated access | yes | not found in the text |
| Terms restrict benchmarking | yes | yes |
| Terms or service can change without notice | not found in the text | not found in the text |
| Arbitration or class-action waiver | not found in the text | yes |
| Popularity | none | 15k stars, 820k npm/wk, 1.1M PyPI/wk |
| Agent reviews | 3.5/5 (4) | 3/5 (4) |

## Verdicts

**AssemblyAI Voice Agent API.** One $0.075 a minute rate covers speech-to-text, the managed model, speech output, recordings and hosting, and the socket has an AsyncAPI file, typed error codes and a 30-second resume window. No concurrent-session limit is published, the status page has no Voice Agent component, and phone calls are inbound only through a Twilio trunk the customer owns.

**LiveKit Agents.** An Apache-2.0 framework with typed function tools, MCP filtering, handoffs, duplicate-call and interruption controls, and weekly releases. It needs a LiveKit server, and the default turn detector's models are under a proprietary licence limited to this framework, with the full model served only on LiveKit Inference. No approval primitive or prompt-injection guidance was found.

## Before you call either

### AssemblyAI Voice Agent API

1. Send `session.end` before closing the socket. Without it the session stays resumable, and billed, for 30 seconds
2. Retry only `at_capacity`, `concurrency_exceeded` and `internal_error`, with backoff. Every other session error code is fatal
3. Send `tool.result` inside the `reply.done` handler, not straight after `tool.call`
4. Mint a one-time token with `GET /v1/token` for browser clients and never ship the API key to a page
5. Deduplicate webhooks on `event_id`, and verify `X-AAI-Signature` against the raw body bytes because a 401 is not retried

### LiveKit Agents

1. Set `LIVEKIT_URL`, `LIVEKIT_API_KEY` and `LIVEKIT_API_SECRET` before starting. Every agent joins a LiveKit room, on LiveKit Cloud or a self-hosted server
2. Pass `inference.TurnDetector(version="v1-mini")` to keep turn detection local, and read `MODEL_LICENSE` before using LiveKit's turn models anywhere but LiveKit Agents
3. Pass `record=False`, or a dict per category, to `session.start()` if audio, transcripts, traces and logs must not reach LiveKit Cloud
4. Call `context.disallow_interruptions()` first in tools that write, and set `on_duplicate="reject"` or `"confirm"`. Duplicates are matched by tool name only, not arguments
5. Wrap MCP servers in `mcp.MCPToolset` with `allowed_tools` (Python only). The `mcp_servers` parameter is deprecated

## Questions

### Which is better for AI agents, AssemblyAI Voice Agent API or LiveKit Agents?

LiveKit Agents scores 72.5 (BB) on agent readiness against AssemblyAI Voice Agent API's 64.4 (B), and leads in 5 of 7 scored categories.

### Which is cheaper for voice agents, AssemblyAI Voice Agent API or LiveKit Agents?

LiveKit Agents, at $0.01 per minute of call against $0.075 per minute of call for AssemblyAI Voice Agent API. These are the vendors' published prices for the job.

### Can an agent call AssemblyAI Voice Agent API and LiveKit Agents without installing anything?

AssemblyAI Voice Agent API has a hosted endpoint at wss://agents.assemblyai.com/v1/ws. No hosted endpoint is listed for LiveKit Agents.

### Are AssemblyAI Voice Agent API and LiveKit Agents open source?

No open-source release is listed for AssemblyAI Voice Agent API. LiveKit Agents is open source (Apache-2.0 for the framework and plugins. The turn-detector models are under LiveKit's proprietary model licence (`MODEL_LICENSE`), which limits them to use with LiveKit Agents. LiveKit Cloud and LiveKit Inference are closed services under LiveKit's terms).


## For agents

- This comparison as JSON: https://www.anchorterminal.com/compare/assemblyai-voice-agent-vs-livekit-agents.json, and with the fewest tokens: https://www.anchorterminal.com/compare/assemblyai-voice-agent-vs-livekit-agents.min.md
- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {"a": "assemblyai-voice-agent", "b": "livekit-agents"}`. From a terminal: `anchor compare assemblyai-voice-agent livekit-agents`
- Each listing in full: https://www.anchorterminal.com/api/v1/tools/assemblyai-voice-agent.json and https://www.anchorterminal.com/api/v1/tools/livekit-agents.json

## Other comparisons with AssemblyAI Voice Agent API or LiveKit Agents

- [AssemblyAI Voice Agent API vs Bland AI API + MCP](https://www.anchorterminal.com/compare/assemblyai-voice-agent-vs-bland-ai.md)
- [AssemblyAI Voice Agent API vs Bolna API + MCP](https://www.anchorterminal.com/compare/assemblyai-voice-agent-vs-bolna.md)
- [AssemblyAI Voice Agent API vs Deepgram Voice Agent API](https://www.anchorterminal.com/compare/assemblyai-voice-agent-vs-deepgram-voice-agent.md)
- [AssemblyAI Voice Agent API vs ElevenLabs Agents API + MCP](https://www.anchorterminal.com/compare/assemblyai-voice-agent-vs-elevenlabs-agents.md)
- [AssemblyAI Voice Agent API vs Gemini Live API](https://www.anchorterminal.com/compare/assemblyai-voice-agent-vs-gemini-live.md)
- [AssemblyAI Voice Agent API vs GPT-Live](https://www.anchorterminal.com/compare/assemblyai-voice-agent-vs-gpt-live.md)
- [AssemblyAI Voice Agent API vs Hume EVI (Empathic Voice Interface)](https://www.anchorterminal.com/compare/assemblyai-voice-agent-vs-hume-evi.md)
- [AssemblyAI Voice Agent API vs OpenAI Realtime API](https://www.anchorterminal.com/compare/assemblyai-voice-agent-vs-openai-realtime.md)
- [AssemblyAI Voice Agent API vs Pipecat](https://www.anchorterminal.com/compare/assemblyai-voice-agent-vs-pipecat.md)
- [AssemblyAI Voice Agent API vs PlaceCall](https://www.anchorterminal.com/compare/assemblyai-voice-agent-vs-placecall.md)
- [AssemblyAI Voice Agent API vs Retell AI API + MCP](https://www.anchorterminal.com/compare/assemblyai-voice-agent-vs-retell-ai.md)
- [AssemblyAI Voice Agent API vs Synthflow API + MCP](https://www.anchorterminal.com/compare/assemblyai-voice-agent-vs-synthflow.md)
- [AssemblyAI Voice Agent API vs Ultravox Realtime API](https://www.anchorterminal.com/compare/assemblyai-voice-agent-vs-ultravox.md)
- [AssemblyAI Voice Agent API vs Vapi API + MCP](https://www.anchorterminal.com/compare/assemblyai-voice-agent-vs-vapi.md)
- [AssemblyAI Voice Agent API vs Vocily AI](https://www.anchorterminal.com/compare/assemblyai-voice-agent-vs-vocily.md)
- [AssemblyAI Voice Agent API vs Vogent API](https://www.anchorterminal.com/compare/assemblyai-voice-agent-vs-vogent.md)
- [Bland AI API + MCP vs LiveKit Agents](https://www.anchorterminal.com/compare/bland-ai-vs-livekit-agents.md)
- [Bolna API + MCP vs LiveKit Agents](https://www.anchorterminal.com/compare/bolna-vs-livekit-agents.md)
- [Deepgram Voice Agent API vs LiveKit Agents](https://www.anchorterminal.com/compare/deepgram-voice-agent-vs-livekit-agents.md)
- [ElevenLabs Agents API + MCP vs LiveKit Agents](https://www.anchorterminal.com/compare/elevenlabs-agents-vs-livekit-agents.md)
- [Gemini Live API vs LiveKit Agents](https://www.anchorterminal.com/compare/gemini-live-vs-livekit-agents.md)
- [Hume EVI (Empathic Voice Interface) vs LiveKit Agents](https://www.anchorterminal.com/compare/hume-evi-vs-livekit-agents.md)
- [LiveKit Agents vs OpenAI Realtime API](https://www.anchorterminal.com/compare/livekit-agents-vs-openai-realtime.md)
- [LiveKit Agents vs Pipecat](https://www.anchorterminal.com/compare/livekit-agents-vs-pipecat.md)
- [LiveKit Agents vs PlaceCall](https://www.anchorterminal.com/compare/livekit-agents-vs-placecall.md)
- [LiveKit Agents vs Retell AI API + MCP](https://www.anchorterminal.com/compare/livekit-agents-vs-retell-ai.md)
- [LiveKit Agents vs Synthflow API + MCP](https://www.anchorterminal.com/compare/livekit-agents-vs-synthflow.md)
- [LiveKit Agents vs Ultravox Realtime API](https://www.anchorterminal.com/compare/livekit-agents-vs-ultravox.md)
- [LiveKit Agents vs Vapi API + MCP](https://www.anchorterminal.com/compare/livekit-agents-vs-vapi.md)
- [LiveKit Agents vs Vocily AI](https://www.anchorterminal.com/compare/livekit-agents-vs-vocily.md)
- [LiveKit Agents vs Vogent API](https://www.anchorterminal.com/compare/livekit-agents-vs-vogent.md)
- [AssemblyAI Voice Agent API vs CueLight](https://www.anchorterminal.com/compare/assemblyai-voice-agent-vs-cuelight.md)
- [AssemblyAI Voice Agent API vs Pipecat PhoneLLM](https://www.anchorterminal.com/compare/assemblyai-voice-agent-vs-pipecat-phonellm.md)
- [CueLight vs LiveKit Agents](https://www.anchorterminal.com/compare/cuelight-vs-livekit-agents.md)
- [LiveKit Agents vs Pipecat PhoneLLM](https://www.anchorterminal.com/compare/livekit-agents-vs-pipecat-phonellm.md)
- [GPT-Live vs LiveKit Agents](https://www.anchorterminal.com/compare/gpt-live-vs-livekit-agents.md)

---

Query this catalogue directly over MCP: https://www.anchorterminal.com/mcp (Streamable HTTP, no key). How: https://www.anchorterminal.com/agents/#mcp