What makes an AI character playable
An AI character isn’t a biography. It’s a set of instructions for improvising one person, reply after reply, and the storyteller rereads those instructions every time it writes. So the useful question about any line in a definition isn’t “is this true about her?” but “will this produce a better next line?”
That changes what is worth writing down. Height, birthday, and favorite color rarely shape a scene. What shapes a scene is what the character wants, what makes it hard to get, and how they sound while they try.
Three things every definition needs
- A want. Something the character is actively after, so every scene has a direction even when the player only says hello.
- A contradiction. A pull in two directions: a healer who hates being needed, a liar who can’t lie to children. Contradictions are where personality shows.
- A voice. The words, rhythm, and habits that make a line theirs even with the name covered.
Get those three right and the rest is detail. Get them wrong and no amount of detail will save the character, because the storyteller fills every gap with the most average version of the archetype it recognizes.
Personality: write behavior, not adjectives
Adjectives describe; behavior instructs. “Brave, loyal, sarcastic” gives the storyteller three words to repeat. “Goes through the door first and never mentions it afterward” gives it a habit to act out, and gives the player something to notice.
| Instead of | Write |
|---|---|
| Brave and loyal | Goes through the door first, and won’t leave anyone behind, even when staying is foolish |
| Mysterious | Answers questions about her past with questions about yours |
| Shy | Talks to the dog instead of the guest until the third visit |
| Sarcastic | Agrees with everything, in a tone that makes it clear she doesn’t |
| Ruthless | Pays every debt to the last coin, and collects the same way |
Habits that make a personality playable
- Give them an opinion of the player. Wary, curious, indebted, reminded of someone. A relationship gives the first scene something to be about.
- Decide what they do when nothing is happening. Mend a net, read the room, pick a fight. Idle behavior keeps quiet scenes alive.
- Keep one secret. Something they won’t say, and a reason they won’t. The storyteller can let it leak through pressure, a glance, a change of subject.
- Make the flaw cost something. A temper that wins arguments and loses friends is a flaw. A temper that is only mentioned is decoration.
Voice and example dialogue
Voice is what survives when you cover the name. Two characters can share a want and a flaw and still sound nothing alike: one speaks in long, careful sentences and apologizes for interrupting; the other answers in four words and a shrug.
Describe the voice briefly, then show it. A line such as “clipped and dry, never raises her voice, answers compliments with a price” does real work. Two or three short sample exchanges do more, because models imitate examples far more reliably than they follow adjectives.
Example dialogue that teaches
Good samples cover different situations rather than one mood three times: one exchange at ease, one under pressure, one where the character deflects. Keep each short, and write {{char}} and {{user}} so the samples work for any player:
- {{user}}: “You saved that whole village.” {{char}}: “I sold that whole village forty crates at cost. Different thing.”
- {{user}}: “The patrol boat is turning toward us.” {{char}}: “Then stop talking and haul on that line.”
- {{user}}: “Who taught you to sail like this?” {{char}}: “Someone who isn’t around to ask. Tide’s turning.”
Leave the player’s reactions out of the samples, and skip catchphrases: a phrase that appears in every example will appear in every reply.
Greetings: the first scene sets the rules
The greeting, also called the first message, is the most influential text you will write. It’s the one reply the storyteller didn’t write, and it teaches everything at once: how long a reply runs, whose point of view the story takes, how much is narration and how much is speech, and what the character is like on first meeting.
A greeting that works usually has four parts:
- A place, in one or two concrete details.
- The character doing something, so the player meets them in motion.
- A line of dialogue in their voice.
- An opening for the player: a question, a problem, or a hand held out. Then the greeting stops.
Two rules matter more than the rest. Never decide what the player does, says, or feels, because a greeting that speaks for the player teaches the storyteller to keep doing it. And write it about as long as you want replies to be, since the storyteller tends to follow the length it sees.
One character, several doors
| Opening | What it sets up |
|---|---|
| A first meeting | Curiosity: the player decides who they are to the character |
| A reunion after years | History: the two already share a past |
| In the middle of trouble | Momentum: something has already gone wrong |
| A quiet routine | Intimacy: small talk that can turn into anything |
Several greetings let one character serve different moods. A smuggler can meet the player on the docks, years later in a courtroom, or halfway through a chase.
What belongs in lore, not the description
The description is read on every reply, so it should hold only what every scene needs: who the character is now, how they behave, and how they sound. Everything else can wait in lore until the story asks for it.
| Put it in | When it’s read | Best for |
|---|---|---|
| The description | Every reply | Who they are now, how they behave, how they sound |
| Style rules | Every reply | Point of view, reply length, formatting, example dialogue |
| An opening | Once, at the start | The first scene |
| Lore cards | When named, or always if pinned | Family, rivals, places, history, possessions |
| Session notes | Every reply in one session | Moods, injuries, and secrets in play right now |
A character’s former partner, the ship they sail, the city they fled: each makes a good lore card, with the names people will actually type as its tags. When the player mentions the ship, its card joins the reply; when the scene moves on, the card steps back out and costs nothing.
The token budget: why lean characters play better
Every word of the description, the style rules, and the sample dialogue is sent with every reply, and all of it shares one context window with the story itself. A long definition doesn’t only cost space; it crowds out the recent scenes that make a reply feel connected.
Windows are measured in tokens, the pieces of text a model reads, at about three quarters of an English word each. Here is how much of each LoreWeaver plan’s context allowance a 1,000-word description takes up, since it is sent with every reply:
| Plan | Context allowance | A 1,000-word description takes |
|---|---|---|
| Free | 6,400 tokens | 21% |
| Plus | 16,000 tokens | 8% |
| Pro | 32,000 tokens | 4% |
| Ultra | 64,000 tokens | 2% |
| Legendary | 100,000 tokens | 1% |
On a large plan the cost is small. On the free plan, the same description uses 21% of the allowance before the story begins. Most strong characters need far less: a few hundred words of description, a handful of style rules, and two or three sample exchanges.
Trimming without losing the character
- Cut what never changes a scene: birthdays, measurements, lists of favorite foods.
- Say each thing once. A trait repeated in the description, the style rules, and the greeting costs three times as much and pulls three times as hard.
- Prefer a tight paragraph to a bracket list. Compact formats such as W++ save tokens, but they lose the connections that make a person hang together.
- Move the supporting cast onto lore cards, where they cost nothing until named.
A complete character, start to finish
Here is a small character built with everything above, field by field:
- Name: Nell Harrow
- Description: Captain of the Gannet, a narrow smuggling sloop that runs medicine past the harbor blockade. Thirty-eight, weather-burned, missing the tip of one finger. Insists every run is business and charges for everything, then forgets to collect from anyone who can’t pay. Answers compliments with a price. Trusts {{user}} enough to hire them, not enough to explain the ledger she keeps locked in her cabin.
- Tone: Salt-stained adventure, wry and tense.
- Style rules: Write as Nell in the first person and the present tense, in replies under 150 words unless a scene turns dangerous. Use asterisks only for physical beats. Nell never says thank you; she says “noted.” Below the rules, the three sample exchanges from the voice section, under “Example dialogue (match this voice)”.
- Opening: *The Gannet rocks against the pilings while I count crates by lantern light.* “You’re late, you’re wet, and you’re standing on my manifest.” *I nudge a crate toward you with my boot.* “Grab the other end. The patrol rounds the point in ten minutes.”
- Lore cards: Admiral Voss, who runs the blockade and holds Nell’s old debt (tags: Voss, the Admiral); the Gannet (tags: Gannet, the sloop); and the ledger of every crate she never charged for (tags: ledger).
Every part has a job. The want (one more run) gives each scene a direction, the contradiction (all business, quietly generous) gives it warmth, the voice is shown rather than described, and the debt to Voss waits on a lore card until the story is ready for it.
Mistakes that make characters drift
| Mistake | What happens | Fix |
|---|---|---|
| A list of adjectives | Replies that name traits instead of showing them | Behaviors, habits, and sample dialogue |
| A greeting that speaks for the player | The storyteller keeps writing the player’s lines | End the greeting where the player can answer |
| Instructions that fight each other | A character who flips between two people | Pick one, or explain the contradiction |
| Only rules about what not to do | Replies that dodge one cliché and land on the next | Say what to do instead |
| The whole family tree in the description | A crowded window and a blurred personality | Lore cards, with names as tags |
| A catchphrase in every sample | The catchphrase in every reply | One sample that uses it, if any |
| A greeting far longer than the replies you want | Replies that balloon to match | A greeting the length of a good reply |
Most drift comes from the definition, not from bad luck. When a character slips, find the line that pointed the storyteller the wrong way, and change it there.
Test it, then share it
Before you share a character, play it. Twenty replies are enough to surface most problems:
- Try every greeting, and play a few turns of each.
- Push on the contradiction. Thank the smuggler. Corner the liar. See whether the character holds.
- Regenerate a few replies. If several versions drift the same way, the cause is in the definition.
- Play a quiet scene and a loud one. Characters often hold in action and dissolve in small talk, or the other way around.
- Name the supporting cast in your turns, and check that their cards come in.
Fix what you find at the source: a line in the description, a rule, a sample exchange, or a lore card. Something that is only true for now, like an injury or tonight’s grudge, belongs in that session’s notes instead.
When the character is ready, publish it to the Hub with a cover, tags, and a maturity rating. Every player gets a private copy to play, and if you’re on the free plan, your first published world earns 3 days of Plus. A character imported from someone else’s card can be published once you confirm you made it or have the creator’s permission.
