Is there an open-source alternative to AI character apps?
Fact-checked, no tracking cookies, and yours to self-host.
Yes, there is one, and here is what it trades away. Agora Cosmica is open source under AGPL-3.0 and run by a small German nonprofit. You talk with the AI Echoes of 30 people from history, from Marcus Aurelius to Frida Kahlo. What you give up is the endless cast. Thirty real people, researched, each with a public factcheck, instead of millions of invented ones.
A library you talk with, not a roleplay app
Most chat-with-a-character apps are built for fun, with invented personas and open-ended roleplay. This is a school, not a stage. The 30 figures are real people from history, philosophers, scientists, mystics, artists, and activists, each with a researched voice and twelve core teachings. Most of what you learn is made ahead of time: narrated life stories, core teachings, four-voice dialogues, and council debates. Talking is one way in, not the whole thing, and every figure is openly an AI Echo, never a recording and never the real person.
How it compares
The character-chat apps are good at what they set out to do. Character.AI has a huge library of invented characters for play. Seneca Chat builds a daily Stoic practice. Hello History reaches a large audience on mobile. Agora Cosmica is the open, nonprofit, fact-checked option in the same space, and it is honest about the tradeoffs: a smaller, curated cast of 30, and a web-first app you can also run yourself.
| Agora Cosmica | Character.AI | Seneca Chat | Hello History | |
|---|---|---|---|---|
| Focus | Philosophy and history, to learn | Invented characters, roleplay | Stoic philosophy, daily practice | Chat with historical figures |
| Open source | Yes, AGPL-3.0 | No | No | No |
| Nonprofit | Yes, a German gGmbH | No | No | No |
| Pricing | 30 free messages a day, then your own key | Free tier and subscription | Subscription | Free tier and subscription |
| Run it yourself | Yes, one command | No | No | No |
| Sources shown | A public factcheck per figure | Not published | Not published | Not published |
Honest, by design
Honest
We are upfront about what this is. Every figure is an AI Echo, an interpretation grounded in primary works and historical context. Never a recording, never claimed to speak for the real person. Each figure ships with factchecks that name what is verified and what is recreated for the story.
Yours
Your conversations stay in your browser, and we never store them on our servers. Bring your own OpenRouter key if you like, and it never touches our servers. No tracking cookies, no third-party analytics, no profiles of who you are. What is yours stays yours.
Open
Live speech runs on our own GPUs in Germany, the rest of the audio on EU hosting, and the whole codebase is open under AGPL-3.0. You can also run it entirely on your own machine. Local Mode points the app at any OpenAI-compatible LLM, like LM Studio, Ollama, or vLLM, and runs the audio stack in docker, so no conversation, voice, or text data ever leaves your computer. So you do not have to trust us. You can check.
Who you can learn from
Thirty figures across 2,500 years. Here are a few. Open any name to explore their life and ideas.
Marcus Aurelius
Stoicism
You will learn to question your first reaction.
Plato
Classical Philosophy
You will learn to examine your own life.
Rumi
Sufi Mysticism
You will learn to let your longing guide you.
Carl Gustav Jung
Depth Psychology
You will learn to meet your own shadow.
Emily Dickinson
American Poetry
You will learn to tell the truth slant.
Albert Einstein
Theoretical Physics
You will learn to keep asking why.
Frida Kahlo
Art & Identity
You will learn to look at yourself without flinching.
Ada Lovelace
Mathematics & Computing
You will learn to see what a thing could become.
Questions people ask
Is there an open-source alternative to AI character apps?
Yes. Agora Cosmica is open source under AGPL-3.0 and nonprofit. You can read every line, audit the privacy claims, or run the whole thing on your own machine. It is built for learning from real historical figures, not for roleplay with invented characters.
Is this an alternative to Character.AI?
If you want an open-source, nonprofit, fact-checked alternative to AI character apps like Character.AI, yes. Agora Cosmica is an education platform for learning from real historical figures, not a companion or roleplay app. It is open source, and it keeps no profile of you.
Can I talk to historical figures with AI?
Yes. You can talk with the AI Echo of 30 figures from history, from Marcus Aurelius to Ada Lovelace and Frida Kahlo. Each Echo is grounded in that person's real writing and ideas. It is an interpretation, clearly labeled, never a recording or the real person.
Is it a nonprofit?
Yes. Agora Cosmica is built by ChipMates gemeinnützige GmbH, a small German nonprofit. There are no shareholders and no profit motive, just the work. The code is open source, and the content moves to a CC-BY license within 6 to 12 months.
How is it different from a roleplay or companion app?
A roleplay or companion app invents a character to play with. Agora Cosmica is an education platform built around real people from history. Each figure is grounded in their own work, and every figure ships with a public factcheck that separates what is verified from what is recreated.
Does it track me?
No tracking cookies, no third-party analytics, and no profiles of who you are. Your conversations stay in your browser and never reach our servers. If you bring your own key, it never touches our servers either. The code is open, so you can check this yourself.
Is it free, and can I run it myself?
You get 30 free messages a day with no signup. Want more, bring your own OpenRouter key. The whole platform is open source under AGPL-3.0, so you can self-host it with one command, and Local Mode runs the model and audio on your own machine.
Where do the facts come from?
Each voice is grounded in primary works and cross-checked sources. Because the Echoes are AI-rendered, what they say will vary, but the source material does not. Where the prose goes beyond the documented record, a public factcheck names what was recreated.
Can I self-host it?
Yes. The whole platform is open source under AGPL-3.0, and one command brings it up on your own machine. Local Mode then points the app at any OpenAI-compatible model, like LM Studio, Ollama, or vLLM, and runs the audio stack in Docker. Nothing you say, type, or hear leaves your computer.
Start a conversation
Open the app and talk with the Echo of any figure. 30 free messages a day, no signup.
Start exploringIf you find this interesting, a star is the simplest way to help us reach more people.Star on GitHub →Not sure where to begin? Start at Where should I start with philosophy?