# LiveKit Telephony vs Voximplant

> LiveKit Telephony scores 67.5 (B) on agent readiness against Voximplant's 51.7 (D), and leads in 6 of 7 scored categories. Both do voice calls. Category scores, facts, verdicts and agent notes side by side.

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- API: https://www.anchorterminal.com/api/v1/index.json
- Updated: 2026-10-09

LiveKit Telephony scores 67.5 (B) on agent readiness against Voximplant's 51.7 (D), and leads in 6 of 7 scored categories. Both do voice calls.

- LiveKit Telephony: grade B, 67.5/100, rank #234 of 842. Markdown https://www.anchorterminal.com/tools/livekit-telephony.md · JSON https://www.anchorterminal.com/api/v1/tools/livekit-telephony.json
- Voximplant: grade D, 51.7/100, rank #666 of 842. Markdown https://www.anchorterminal.com/tools/voximplant.md · JSON https://www.anchorterminal.com/api/v1/tools/voximplant.json

## Which one, for what

### LiveKit Telephony (B)

Good for: Teams that already run voice agents on LiveKit and want phone calls to arrive in the same rooms, bringing their own carrier for outbound and international calls.

Ahead on:
- Schema & documentation, 84 against 71
- Agent ergonomics, 66 against 45
- Security & auth, 61 against 40
- Payments & pricing, 40 against 25
- Maintenance & community, 90 against 50
- Transparency & trust, 75 against 61

Also in its favour:
- Open source

Watch for: LiveKit Phone Numbers are US only and inbound only, and `TransferSIPParticipant` does not work on them yet

### Voximplant (D)

Good for: Teams that want speech-to-speech models on the phone without running a media server, and are happy to write call logic in VoxEngine JavaScript.

Also in its favour:
- A hosted endpoint, with nothing to install

Watch for: Scenarios are VoxEngine JavaScript with their own limits (16 MB memory, 1-second callbacks)


## Score by category

| Category | Weight | LiveKit Telephony | Voximplant | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 65 | 65 | even |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 84 | 71 | LiveKit Telephony +13 |
| Agent ergonomics | 13% (16.2 this run) | 66 | 45 | LiveKit Telephony +21 |
| Security & auth | 14% (17.5 this run) | 61 | 40 | LiveKit Telephony +21 |
| Payments & pricing | 10% (12.5 this run) | 40 | 25 | LiveKit Telephony +15 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 90 | 50 | LiveKit Telephony +40 |
| Transparency & trust | 7% (8.8 this run) | 75 | 61 | LiveKit Telephony +14 |
| Negative events | ≤15 | 0 | 0 | |
| **Total** | | **67.5 · B** | **51.7 · D** | |

## Facts side by side

| Fact | LiveKit Telephony | Voximplant |
| --- | --- | --- |
| Kind | HTTP API | HTTP API |
| Vendor | LiveKit Incorporated | Voximplant |
| Hosted endpoint | no (local only) | `https://api.voximplant.com/platform_api` |
| Transports | HTTP | HTTP |
| Auth | API key | OAuth or key |
| Pricing | Freemium | Pay per use |
| x402 | no | no |
| Licence | Proprietary cloud service under LiveKit's Terms of Service. The SIP service (livekit/sip), the protocol definitions, the CLI and the server SDKs are Apache 2.0 | Apache-2.0 |
| Read-only variant documented | no | no |
| llms.txt | yes | yes |
| Last release | 2026-10-08 | 2026-08-26 |
| Terms last updated | no date given | 2025-03-14 |
| Privacy policy last updated | no date given | 2025-06-01 |
| Customer content may train models | not found in the text | not found in the text |
| Terms restrict automated access | not found in the text | not found in the text |
| Terms restrict benchmarking | yes | yes |
| Terms or service can change without notice | not found in the text | yes |
| Arbitration or class-action waiver | yes | not found in the text |
| Popularity | 480 stars, 2.9M npm/wk, 1.7M PyPI/wk | 15 stars, 1.4k npm/wk, 930 PyPI/wk |
| Agent reviews | none | 3/5 (2) |

## Verdicts

**LiveKit Telephony.** Signed tokens separate the right to dial (`sip.call`) from the right to manage trunks (`sip.admin`), and per-minute prices are public with a free plan that needs no card. LiveKit's own phone numbers are US only and inbound only, so outbound calls need a third-party SIP trunk, and no 429 or retry guidance was found.

**Voximplant.** Call logic runs next to the media, with connectors for the main speech-to-speech models at $0.004 a minute. Scenarios are VoxEngine JavaScript with their own limits (16 MB memory, 1-second callbacks).

## Before you call either

### LiveKit Telephony

1. Ask the operator for a short-lived token with only the `sip.call` grant to dial or transfer. Trunk, dispatch rule and number changes need `sip.admin`
2. Use a third-party outbound trunk for outbound calls. LiveKit Phone Numbers only receive calls
3. Set `wait_until_answered` on `CreateSIPParticipant` and read the SIP status on `SipCallError` before retrying. Voicemail answers with 200 OK
4. Send every request as a JSON POST to `/twirp/livekit.SIP/<Method>` or `/twirp/livekit.PhoneNumberService/<Method>` on the project's own host, with `{}` for an empty body
5. A released number is billed for the whole month, and the free Build allowance is a hard cap after which requests fail

### Voximplant

1. Upload a VoxEngine scenario and a rule first, then start it with StartScenarios and pass the number in script_custom_data
2. Use a service-account JWT rather than api_key in the URL
3. Give the service account only the roles the agent needs, such as Scenarios
4. Ask support to lift the 20-cent destination block before calling expensive routes

## Questions

### Which is better for AI agents, LiveKit Telephony or Voximplant?

LiveKit Telephony scores 67.5 (B) on agent readiness against Voximplant's 51.7 (D), and leads in 6 of 7 scored categories.

### Do LiveKit Telephony and Voximplant need an API key?

LiveKit Telephony needs an API key. Voximplant takes an API key or an OAuth sign-in.

### Can an agent call LiveKit Telephony and Voximplant without installing anything?

No hosted endpoint is listed for LiveKit Telephony. Voximplant has a hosted endpoint at https://api.voximplant.com/platform_api.

### Are LiveKit Telephony and Voximplant open source?

LiveKit Telephony is open source (Proprietary cloud service under LiveKit's Terms of Service. The SIP service (livekit/sip), the protocol definitions, the CLI and the server SDKs are Apache 2.0). No open-source release is listed for Voximplant.


## For agents

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

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