The Character Card Was Never the Character
AI companions are usually built on a single document — a system prompt, a JSON persona, a character card — that tries to hold identity, values, style, and behavior all at once. A closer look at character card ecosystems, lorebooks, memory architectures, and persona-drift research suggests that document is doing too many jobs, and that the real fix looks less like a better file format and more like a small compiled runtime that sits between a human-authored personality and the model.
AI CompanionsMemory ArchitectureAI agentsprompt engineering
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