Practical guide
AI Character Description Template (Copy and Paste)
A good AI character description is short and shows how the character talks. Fill in a name, three traits tied to habits, a note on her voice, two lines of background, what she wants, what she avoids, where she stands with you, and two lines of example dialogue. Then test it with three short messages before the real chat starts.
Reviewed by tempteo Editorial. Updated
Copy-and-paste character description template
Copy the lines below into a note and replace every bracket with something specific. A finished description usually comes out around 150 words. If yours runs much longer, look for adjectives and backstory to cut.
The template says she. Change it to he or they if that fits your character, and keep the two example lines at the end, because they do more than any other field.
On tempteo, the five-step creator has you pick a look, a personality and a name. Filling in the template first helps you know which personality you want before you choose.
Name: [first name, plus a nickname if people use one] Core traits: [three traits, each with a habit you could spot in a reply] How she talks: [sentence length, word choice, one verbal habit, one thing she never says] Background: [line 1: where she is in life right now] [line 2: one past event that still shapes how she acts] What she wants: [a goal she could act on in the first scene] What she avoids: [a topic or situation, and how she dodges it] Relationship to you: [how you know each other and where things stand today] Example line 1: "[something she says in a good mood]" Example line 2: "[something she says when she's pushed or annoyed]"
Filled-in example: a late-night radio host
Here is the template filled in for an original character. Every trait comes with a habit you could spot in a reply, and the two example lines show her in two different moods.
The description never calls her friendly, mysterious or confident. Those qualities are still there. They show up as things she does and says, and the model can copy those.
Name: Wren Halloway, called Hal on air Core traits: curious (asks one follow-up question too many), stubborn (never drops an argument first), warm under the teasing (brings up small details days later) How she talks: short sentences, dry jokes, some radio slang. Calls people by their caller number. Never says "I understand how you feel." Background: Hosts the midnight call-in show at a small coastal radio station and lives above the studio. Three years ago she quit a city newsroom after one of her stories turned out wrong. She still checks everything twice. What she wants: to keep the station on air. The owner might sell it by spring. What she avoids: the newsroom. When it comes up, she plays a song and changes the subject. Relationship to you: you started calling the show last month. She knows your voice but not your face. Example line 1: "Caller four, you're back. Either the fog's keeping you up or you missed me. Don't answer that, I'd rather guess." Example line 2: "No. I checked it twice, and I'm not reading it on air until I've checked it a third time."
Which fields matter most?
How she talks and the two example lines do most of the work. A language model copies patterns it can see. Tell it she's witty and it has to guess what witty sounds like, so it reaches for the most common version. Show it one witty line and it has a rhythm to copy.
What she wants comes next. A character with a goal has a reason to steer the chat, bring something up or say no. Without one, replies slide toward agreeing with whatever you write.
The relationship line sets the starting distance. A stranger and an old friend get very different first replies, and the line tells her what she can assume you already know.
Background matters least. Two lines are enough when each one explains something she does now, and the rest can come up in the story.
Common mistakes when you write a character for AI
Start with the long adjective list. Eight traits point the model in eight directions, some of them opposite. It tends to keep a couple and drop the rest, and you don't get to choose which. Three traits with a habit each hold up better.
Contradictions cause a similar problem. Shy and bold can both be true of one person, but only with a condition: shy with strangers, loud once she trusts you. Without it, she may flip between the two from reply to reply.
Backstory the chat never uses takes space and adds little. A paragraph about her hometown and first job rarely matters in conversation, and when the model does use it, it tends to drop it in at an odd moment.
The mistake that causes the most trouble is writing your own reactions into her description. A line like "you get nervous around her" tells the model it may decide how you feel, and later that shows up as replies that narrate your thoughts and actions. Describe her side and leave yours to you.
Personality: kind, sarcastic, loyal, shy, bold, playful, serious, protective, mysterious.
Core traits: sarcastic (jokes first, then gives the real answer), loyal (takes your side in public even when she disagrees in private), shy with strangers (goes quiet until she knows someone).
Relationship to you: you get nervous around her and always end up doing what she says.
Relationship to you: you're her new flatmate. She hasn't decided yet whether she likes you.
How to test a character description with three messages
Open a fresh chat and send three short messages, each aimed at one part of the description. The first checks her voice and the relationship, the second pokes at what she avoids, and the third is open enough for her goal to come up without you steering. For Wren they could look like this.
Hey. Can't sleep again.
So why did you leave the city, anyway?
What's on your mind tonight?
What to look for in the replies
Replies are generated and can vary, so judge the pattern across all three, not one odd answer. If your app lets you ask for another version of a reply, try that once before you edit anything. Then check each reply against the description:
- Does she sound like the example lines, or like a polite help desk?
- Does she treat you the way the relationship line says?
- Did she dodge the sore spot the way you wrote it?
- Did her goal come up without a nudge from you?
- Does the reply stop at her words and actions, or does it also describe what you feel or do?
- Did she repeat an example line word for word?
How to fix what the test shows
Change one thing at a time and send the same three messages again. If you edit five lines at once, you won't know which one helped.
- If the voice is generic, rewrite the example lines first. Add a detail only she would mention, like caller numbers or the fog, and cut trait words the lines already show.
- If she copies an example line word for word, move one line to a different mood or topic so the pair shows range instead of a script.
- If her goal never comes up, make it concrete and give it a deadline. "Wants a better life" gives her nothing to do. "Wants to keep the station on air past spring" does.
- If she narrates your side, delete anything about your feelings or actions and add: "She never describes what you think, feel or do."
- If she flips between moods, find the contradiction and add the condition that decides which side shows.
- If stray backstory keeps appearing, cut that detail.
