AI prompt generator & vs Character AI

Two Artificial intelligence APIs with a free plan, compared field by field.

AI prompt generator & optimisation API Character AI — create custom characters & chat
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Paid from $9.99 $9.99
Updated 2025-11-26 2025-11-26

AI prompt generator & optimisation API

The API rewrites a prompt to use fewer tokens, enforces a JSON schema on the output and improves answer quality without changing intent. Cost is the measurable part.

It works against OpenAI, Claude, Gemini, Llama and Mistral, so the same optimisation applies whichever model is behind the product.

Open AI prompt generator & optimisation API →

Character AI — create custom characters & chat

The API creates a character with a defined personality, traits and backstory, and keeps it consistent across a conversation.

Games, companion apps and interactive fiction use it where a generic assistant would break immersion.

Open Character AI — create custom characters & chat →

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Updated 2025-11-26 by Bilgisam Ltd. About