Intervo AI
One of the few voice agent platforms where you can read the source and move the whole thing in-house if the hosted pricing turns against you. Model and voice vendors are swappable rather than locked, which keeps per-minute costs negotiable. The catch is that the headline monthly price is quoted against a struck-through number, which is a discount that has been running long enough to be the real price.
Pros
- Source is public on GitHub, so self-hosting is a real fallback rather than a promise
- Model provider and voice engine are picked independently, covering OpenAI, Anthropic, Google, ElevenLabs and Azure
- Integrations cover Intercom, Zapier, Google Sheets, Cal.com and generic webhooks out of the box
- A free tier with three agents makes evaluation possible without a card
Cons
- The 129 USD plan is displayed as a permanent discount off a much larger list price, so the real anchor is unclear
- No country or registered address is published for Codedesign, Inc.
- Self-hosting shifts integration, security and compliance costs onto you, as the vendor itself notes
- Stated 90 to 95 percent accuracy is vendor-reported and conditioned on ideal audio