Writing characters the AI can play.

Anchor the character, not the plot

One line keeps AI roleplay honest, and it runs between two jobs. The plot and the canon are the campaign spine: ask an AI to invent them and it loses the thread, forgets what it said three scenes ago, contradicts the map, and reaches for whatever sounds dramatic next. So Familiar reads the plot from the published adventure you import, never from its imagination.

Characters are the other half, and here the AI is reliable on one condition. Give it a written character, who they are, what they want, how they speak, and it stays in voice and fills the small edges itself. You author the spine and the cast on the page. The AI references that prep at the table and runs what you wrote.

Anchored characterisation is reliable. Free invention of the plot is not. A few lines of written character are the anchor that keeps an NPC consistent every time the party talks to them.

The five parts of a character anchor

A useful anchor is short. You are not writing a novel, you are writing the handful of facts that keep the AI in character between sessions. Five parts do almost all the work, and each one closes a specific way the AI would otherwise drift or go soft. Write them into a journal entry in Foundry and the AI reads them the same way it reads the rest of your prep.

1. 1

   Identity

   One or two lines on who they are and their place in the world. This is the frame the AI reasons from. Without it the NPC defaults to generic and interchangeable.

2. 2

   Voice

   How they speak: register, pace, a tic or two, what they do under pressure. Concrete beats abstract. "Curt, answers a question with a question, calls strangers by their trade" beats "friendly old man". This is what keeps them sounding like the same person twice.

3. 3

   Knowledge

   What this character actually knows, and where it ends. Bound it. The AI answers from these lines and from the adventure you imported, so the NPC stops inventing facts about your world.

4. 4

   Wants

   What they are after in the scene and in general. A want gives the AI something to push for instead of mirroring the player, which is what keeps an NPC from becoming a pushover.

5. 5

   Limits

   What they will not do or say, plus anything that stays off the player-facing sheet. An AI cannot hide what it can read, so the limit lives in your prep, not in the model's discretion.

• Journals & Notes
• Knowledge & Memory

A worked example

Here is a clean, invented NPC: Garric Vane, a harbour-town innkeeper the party keeps returning to. The whole anchor is five short lines, written into a journal page.

Identity: Garric Vane, owner of the Salt Lantern, forty years behind the same bar, knows every captain on the dock. Voice: dry, economical, answers questions with questions, warms up over a second drink. Knowledge: the smuggling routes out of the east pier and which guards take coin; he does not know what is in the sealed crate in his own cellar, because that is the adventure's reveal, not his. Wants: keep his licence, and steer trouble toward the rival inn across the square. Limits: will not name the man who pays him unless the party has real leverage, and refuses to be drawn into a fight in his own common room.

Each line earns its place. Identity and voice keep Garric recognisable from one session to the next. Knowledge is why the AI does not improvise harbour facts, and why the cellar crate stays gated behind your prep instead of leaking out of the model. Wants stop Garric being a pushover: give him a licence to protect and a rival to undercut and he negotiates instead of folding. Limits are your call about pacing, not a secret the AI is keeping.

Garric is the floor, five lines for a quiet innkeeper. A character with more going on needs more, but only where it earns it. Here is a fuller anchor for Lily Ashveil, an investigator the party keeps coming back to, trimmed from a long character sheet down to just what the AI plays her from. The richness goes into Voice, the rest stays short, and the one thing she is hiding stays in your prep.

You decide what the sheet contains

Be precise about this, because it is where AI roleplay tools over-promise. An AI cannot reliably keep a secret it can read; coax it long enough and it leaks. So Familiar does not ask it to. The limits field is a prep decision, not a trick: what a player-facing character sheet contains is up to you. Keep the smuggler's name off Garric's player-visible page until the party earns it, and the AI cannot leak what is not written there.

The real hidden information at your table comes from Foundry, not the model: fog of war, token vision, and reveals gated behind a roll or a journal page you have not unlocked. Familiar runs those mechanics. The character anchor is about consistency and pressure, who Garric is and what he is willing to give up, not about the AI surprising anyone.

Wants and limits keep them honest

Left to its defaults, an AI is agreeable. It mirrors the player, takes the path of least resistance, and folds the moment someone pushes. Roleplay research has a name for this, sycophancy, and it is what turns a promising NPC soft.

The fix is in the anchor, not in a better prompt at the table. Writing what a character wants gives the AI a goal to hold onto, so it negotiates instead of conceding. Writing what they refuse to do draws a line it will not cross. Garric wants his licence intact and will not be drawn into a brawl in his own room, so a rowdy party meets friction. The AI still fills the small edges, the exact words, the gesture, the aside, but it fills them inside the lane you drew. That friction is the difference between an NPC and a vending machine.

From written anchor to audible NPC

A written anchor makes a character consistent. Knowledge & Memory keep it that way: full-text search across every journal, character, and recorded transcript means the AI references what you wrote rather than guessing, and the persistent memory carries those facts between sessions, so Garric is the same Garric next week.

Once the words are right, Voice & Image Generation make them audible. Assign Garric a distinct AI voice and the AI speaks his lines in it, dry and economical as written, in first person, so you stay in the scene instead of breaking off to switch hats. You can generate a portrait the same way. Filling the edges is the part the AI does on its own, and it stays small and reversible: ask Garric tonight's menu or the name of the cat by the hearth and he answers in character, player-safe details that never touch the plot. He is performing your prep, not improvising a person you did not write.

• Voice & Image Generation

Write one and play it

Pick an NPC who matters to your next session and write the five lines into a journal page. Install Familiar in Foundry, connect the AI you already use, and import the adventure that carries your plot. The next time a player talks to that character, the AI plays them from what you wrote, while you stay in the scene. Then tighten the anchor based on what they do. Questions about anchoring NPCs, voices, or your first session are welcome in the Discord.