How It Works

Every character on Vesper has a full psychological profile — attachment style, defense mechanisms, core beliefs, archetypes — built from source material and analyzed across six therapeutic frameworks. Their responses emerge from that psychology, not a script.

This means they can surprise you. The same character under different emotional pressure will respond in genuinely different ways. You can't map their range in five minutes.

This is a closed beta. Mess around as much as you want.

Pick a character and start talking. That's it. You don't need to prompt-engineer or set up anything. The character's psychology is already loaded.

A few things to know:

• They have memory. Your conversations are saved. They remember what you talked about, what pushed their buttons, what made them open up.

This is one of the features that makes Vesper unlike anything else. Tap the 🧠 brain icon on any message to see the character's internal state — what they're thinking before and after they respond.

Reflections are generated by a separate system from the character's response — they're genuine internal processing, not performance. Think of it as seeing someone's therapy notes alongside their conversation.

Characters remember you across conversations. Every interaction is scored for psychological significance — moments that moved the character emotionally are tagged as high-salience and persist. Start a new conversation and they know who you are and what you've been through together.

When you're ready, open the character panel and tap Process Memories. This triggers a subconscious processing cycle — modeled on how the brain consolidates memory during sleep. Two things happen:

Tap the menu icon (top right of the chat) to open the character panel. Here you'll find:

• Conversations — all your chat threads with this character. Start new ones, switch between them, delete old ones.
• Memory — tap the memory badge to see what the character remembers. Color-coded by emotional valence, with timestamps and excerpts.
• Force Vectors — four dimensions that define how the character relates to you right now. Power (dominant ↔ submissive), Intimacy (connecting ↔ distancing), Conflict (aggressive ↔ harmonious), Deception (authentic ↔ manipulative). These shift across conversations.
• Evolve Psychology — the button that triggers psychological evolution (see above).

• Don't treat it like ChatGPT. These characters aren't trying to be helpful. They have their own agenda, moods, and boundaries. Push an avoidant character and they'll pull away. Be genuine with an anxious one and they'll cling.
• Ask about their world. These characters know their universe — the people in their lives, their memories, their relationships. Ask Hamlet about Ophelia. Ask Dracula about Van Helsing. Ask Shadowheart about Shar. For generated characters, their world comes from their journal — the formative experiences, the people who shaped them. The deeper you go into their story, the more the psychology surfaces.
• Try the darker characters. Iago, Lady Macbeth, Hannibal — characters that are uncomfortable to talk to. The psychology is most visible when there's friction.
• Check the reflections. The pre/post reflection cards are where you see the engine at work. If you're wondering why a character said something, the post-reflection usually explains it.
• Evolve after meaningful conversations. Don't evolve after small talk. Have a real interaction — push boundaries, build trust, create conflict — then evolve. The delta will be more interesting.
• We're in beta. Things might break. If a character gives a weird response, try sending another message. If something feels off, let us know.