La Lettre Portal
The engine — the machine that keeps the AI on a leash

An AI that invents, within a frame written by humans.

An artificial intelligence is very good at improvising a conversation. But it does not know how to hold a story to the end. Our engine leaves it a lot of freedom for the details, while checking at every moment that it stays true to what the authors wanted.

Four circles, from the tightest to the freest

Imagine a target. The closer you are to the centre, that is, to the heart of the story, the less the AI is allowed to invent. The further you move towards the edge, the freer it is.

AI freedom 0

The centre: what never moves

The facts, the tipping points, the changes, the last line. Written by the authors, full stop.

AI freedom 0–1

The state of the story

The eight dials (debt, trust, shame…) and what the characters remember about each other.

AI freedom 2–3

The actors' performance

The exact words, the small gestures, the rhythm, the little surprises.

AI freedom 4

The scenery

The atmosphere, the people passing by, the light, the texture of things.

The freedom scale, from 0 to 4

LevelWhat the AI is allowed to do
0Nothing: it is written by the authors, and the AI recites it as is.
1Change the way of saying it a little, not the substance.
2Choose the words and add small gestures.
3Find its own tricks and cause small surprises.
4Invent widely, as long as the tipping point and the change stay the same.

Each character's nature

The machine knows what a character can say, but also what they would almost never say. Dialogue can vary a lot from one game to the next, without the character ceasing to be themselves.

The unavoidable passages

What moment M07 means, the sacrifice that has to be made in M08, the last line of M10: the machine brings these moments to life, but it does not invent their meaning. That is the authors' job.

We show it, we do not hand it over. The engine is a precious, protected asset. It can be demonstrated, but its full instructions do not leave the building. Only a summary, frozen, is shared, under agreement.