Hume EVI Is Shutting Down - Moving Your Voice Characters to Neocortex

Hume AI's Empathic Voice Interface (EVI) was one of the most interesting voice APIs of the last two years, with replies that adapted their tone to how the user sounded.

Hume's documentation now carries a clear notice: Hume is sunsetting the TTS and EVI APIs. Access ends on November 13, 2026, and account data is permanently deleted after that date.

If you have characters running on EVI, you have a few weeks to move them.

What you need to replace

An EVI integration usually covers:

1. Speech in. Transcribing what the player says.
2. A language model. EVI 3 and EVI 4-mini work with partner LLMs.
3. Expressive speech out. A voice that sounds like it means what it says.
4. A system prompt that defines the character.

Hume never shipped a Unity SDK, so if you used EVI in a game, you also built your own client around its Python, TypeScript or React SDKs.

Hume EVI vs Neocortex

Moving a Hume character to Neocortex

1. Create a free Neocortex account.
2. Turn your system prompt into nodes. Background becomes the Agent node, facts become Knowledge, the character's temperament becomes Personality and a starting Emotion.
3. Recreate the voice. Clone it from a recording you have the rights to, or describe it and pick from generated voices.
4. Talk to it in the browser to check it sounds right.
5. Connect your client. Use the Unity SDK, the Unreal plugin, or the Web API from any other stack.

Most characters move in an afternoon. Emotion tags on every reply mean you can still drive facial animation and tone in your game.

Do not leave it to the last week

After November 13, your EVI integration stops working and your Hume data is deleted. Start your migration now, or contact us if you need help moving a larger project.

Hume details are from Hume's documentation, checked October 2026.