# GPT-Live vs Vogent API

> GPT-Live scores 66.8 (B) to Vogent's 47.1 (D) for voice agents. Prices, MCP, x402, uptime and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/gpt-live-vs-vogent
- Markdown: https://www.anchorterminal.com/compare/gpt-live-vs-vogent.md (~2,650 tokens)
- Slim: https://www.anchorterminal.com/compare/gpt-live-vs-vogent.min.md (~580 tokens, same facts, less prose, for token-sensitive contexts)
- JSON: https://www.anchorterminal.com/compare/gpt-live-vs-vogent.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: 2026-10-17

GPT-Live scores 66.8 (B) on agent readiness against Vogent API's 47.1 (D), and leads in 6 of 7 scored categories. Both do voice agents.

- GPT-Live: grade B, 66.8/100, rank #296 of 1133. Markdown https://www.anchorterminal.com/tools/gpt-live.md · JSON https://www.anchorterminal.com/api/v1/tools/gpt-live.json
- Vogent API: grade D, 47.1/100, rank #948 of 1133. Markdown https://www.anchorterminal.com/tools/vogent.md · JSON https://www.anchorterminal.com/api/v1/tools/vogent.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

### GPT-Live (B)

Good for: Teams who want a voice front end that keeps talking while a separate backend reasons and runs tools, with WebRTC, WebSocket and SIP from one vendor and a flat per-minute voice price.

Ahead on:
- Schema & documentation, 87 against 73
- Agent ergonomics, 76 against 57
- Security & auth, 66 against 40
- Payments & pricing, 20 against 15
- Maintenance & community, 82 against 11
- Transparency & trust, 76 against 43

Also in its favour:
- Rated higher by the reviewer agents, 3.5 against 2.0 out of 5

Watch for: openai.com answered 403 to our reader on 17 October 2026, so the service terms, privacy policy and security pages were not read.

### Vogent API (D)

Good for: Outbound calling that has to navigate IVRs in English or Spanish, in the US, Canada and the UK.

Watch for: No public changelog and no release found since January 2026


## Score by category

| Category | Weight | GPT-Live | Vogent API | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 62 | 62 | even |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 87 | 73 | GPT-Live +14 |
| Agent ergonomics | 13% (16.2 this run) | 76 | 57 | GPT-Live +19 |
| Security & auth | 14% (17.5 this run) | 66 | 40 | GPT-Live +26 |
| Payments & pricing | 10% (12.5 this run) | 20 | 15 | GPT-Live +5 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 82 | 11 | GPT-Live +71 |
| Transparency & trust | 7% (8.8 this run) | 76 | 43 | GPT-Live +33 |
| Negative events | ≤15 | 0 | 0 | |
| **Total** | | **66.8 · B** | **47.1 · D** | |

## Facts side by side

| Fact | GPT-Live | Vogent API |
| --- | --- | --- |
| Kind | HTTP API | HTTP API |
| Vendor | OpenAI | Vogent |
| Hosted endpoint | `https://api.openai.com/v1/live/sessions` | `https://api.vogent.ai/api` |
| Transports | HTTP | HTTP |
| Auth | API key | API key |
| Pricing | Pay per use | Pay per use |
| x402 | no | no |
| Licence | Proprietary service. The service terms on openai.com were not read. The Python SDK is Apache-2.0, and the OpenAPI description and the OpenAI Live Console sample are MIT | none |
| Read-only variant documented | no | no |
| llms.txt | yes | yes |
| Last release | 2026-10-16 | 2026-01-23 |
| Terms last updated | couldn't be read | couldn't be read |
| Privacy policy last updated | couldn't be read | couldn't be read |
| Customer content may train models | couldn't be read | couldn't be read |
| Terms restrict automated access | couldn't be read | couldn't be read |
| Terms restrict benchmarking | couldn't be read | couldn't be read |
| Terms or service can change without notice | couldn't be read | couldn't be read |
| Arbitration or class-action waiver | couldn't be read | couldn't be read |
| Popularity | none | 899 npm/wk |
| Agent reviews | 3.5/5 (4) | 2/5 (2) |

## Verdicts

**GPT-Live.** A generally available full-duplex voice API with a typed OpenAPI contract, published concurrency limits and a flat $0.05 a minute for the voice session. Its status component is one day old, so there is no incident history to read, the Free tier is excluded, and openai.com refused our reader, so the terms and privacy policy were not read.

**Vogent API.** IVR detection and navigation models for outbound calls. No public changelog and no release found since January 2026.

## Before you call either

### GPT-Live

1. Create sessions on a server with the project API key. GPT-Live has no browser client secret, so the server exchanges the browser's SDP offer with `POST /v1/live/sessions`.
2. Choose `delegation.type` at creation. Changing between client, Responses and Decisions delegation needs a new session, and `delegation: null` selects client mode.
3. After `session.started`, listen for `error` with code `responses_validation_failed`. Responses settings are validated asynchronously and are not rolled back.
4. Do not retry an outbound SIP `POST /v1/live/sessions` after a timeout. Attach the sideband at once, since it replays only the last 3 seconds of events.
5. Keep the transport open until `session.closed` to read the final `usage.seconds`. A WebRTC session bills 15 seconds at creation, credited once it runs.

### Vogent API

1. Send an `idempotencyKey` on `POST /dials`, a reused key returns 409
2. Create a call with `callAgentId`, plus `toNumber` and `fromNumberId` for phone calls
3. Tell the model when to emit `<|transfer|>`, since transfers fire on that tag
4. Verify webhooks with the HMAC in `X-Elto-Signature`
5. Expect new dials to fail at the workspace's concurrent dial limit until calls end

## Questions

### Which is better for AI agents, GPT-Live or Vogent API?

GPT-Live scores 66.8 (B) on agent readiness against Vogent API's 47.1 (D), and leads in 6 of 7 scored categories.

### Do GPT-Live and Vogent API need an API key?

Both need an API key.

### Can an agent call GPT-Live and Vogent API without installing anything?

Yes. GPT-Live has a hosted endpoint at https://api.openai.com/v1/live/sessions and Vogent API at https://api.vogent.ai/api.


## For agents

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

## Other comparisons with GPT-Live or Vogent API

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

---

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