concept

Character card

A character card is a structured description of a character used in AI roleplay — name, appearance, personality, backstory, speaking style — loaded as the system prompt at the start of a conversation.

Character cards (used by Character.ai, SillyTavern, NovelAI Persona) bundle the static character context that the LLM needs to roleplay convincingly. Typical format: name, description, personality traits, sample dialogue, scenario, knowledge constraints, speech mannerisms. Loaded as the system prompt, the card defines the character for the duration of the chat. Quality of character cards is the single largest determinant of roleplay quality — strong cards produce convincing characters even on weaker models; weak cards confuse frontier models.

When to use character card

Any AI roleplay platform.
Character chat agents.

Common mistakes

Card too long — bloats context every turn.
Contradictory traits — model picks one and ignores the other.

FAQ

What is character card?

When should I use character card?

Any AI roleplay platform. Character chat agents.

What are the most common mistakes with character card?

Card too long — bloats context every turn. Contradictory traits — model picks one and ignores the other.

AI roleplay (LLM) — AI roleplay is the use of language models for interactive fiction, character chat, and collaborative storytelling — usually with a persistent character persona maintained across many turns.
System message — A system message is the highest-priority instruction message in a chat-style API call — used to set role, constraints, and behaviour for the entire conversation.
Persona prompting — Persona prompting is the practice of assigning the model a specific identity, expertise, and audience in the system prompt to steer voice, tone, and answer depth.

Last updated: 2026-06-01. Raw markdown: https://promtable.com/glossary/character-card.md.