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Chat features

Custom Personas

Oneaccount,manyvoices

Study partner, deep-work coach, creative collaborator, professional assistant — build a persona for every mode you work in, and switch between them instantly.

📚

Study Partner

Homework & tutoring

🎯

Deep Work Coach

Focus & accountability

✍️

Creative Voice

Worldbuilding & roleplay

💼

Work Assistant

Drafts & research

The just4o.chat create-persona modal showing persona name, purpose, and file context fields.

Personas are created inside the product, with room for a name, purpose, pasted context, and supporting files.

🎯

Deep Work Coach

I keep getting distracted from my writing project.
Let's fix that. How long can you commit right now — 25 or 50 minutes? Close everything except your doc. I'll check in when the timer ends.
25 minutes works.
Timer starts now. One goal: 300 words. Go.

What you get

Built for real workflows

Each persona is more than a name. It is a reusable layer of behavior, context, and memory you can call back into whenever that mode of work matters.

Per-persona memory

Each persona keeps its own memory context. Your study notes stay in your study persona, your character lore stays in your creative persona.

Works across models

Your persona configuration survives model switches. Switch from Claude to GPT-4o and the voice stays consistent.

Build from scratch or files

Start with a short purpose brief, attach files for extra context, or paste your own text to shape the voice exactly how you want it.

Reusable across projects

Assign a persona to any project or chat. Switch personas mid-session without losing your place or your context.

Getting started

Up and running in minutes

Create your first persona and have it active in a live chat in under two minutes.

  1. 1

    Create in Account → Personas

    Give your persona a name, a purpose, and optional files or context. Done in under a minute.

  2. 2

    Switch in any chat or project

    Pick your persona from the conversation toolbar. The voice, tone, and memory activate immediately.

  3. 3

    Refine over time

    Update the persona as you learn what works. Instructions, files, and persona memory can all evolve with the workflow.

No identity bleed

What stays in one persona, stays there

Personal reflections don't leak into your work assistant. Character lore doesn't show up in your study sessions. Each persona's memory is fully scoped and isolated from every other.

Build the AI that fits your life

Create your first persona free. Add as many as your plan allows.

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