KinetiNode/claude-fable-5-system-prompt-clean

What it is – A set of three Markdown files (core.md, balanced.md, complete.md) that contain a vendor‑neutral version of Anthropic’s Claude Fable 5 / Mythos 5 system prompt. The original Claude‑specific scaffolding (XML wrappers, tool interfaces, product‑specific notes, etc.) has been removed, leaving only the behavioral guidance that transfers well to other frontier LLMs.

Purpose – Reduce prompt size for better context efficiency while preserving high‑impact principles such as understanding user intent, honest uncertainty handling, clear communication, high‑quality code generation, verification before answering, objective error correction, and avoiding unnecessary meta‑commentary.

Compatibility – Designed to work with Claude, ChatGPT, Gemini, DeepSeek, Qwen, Grok, GLM, and other instruction‑following large language models.

How to use – Copy the contents of the desired file into the model’s system prompt or system instructions field (API) or into custom‑instruction / custom‑GPT / Gems‑style fields in consumer interfaces.

Philosophy – Not meant to replace or improve Anthropic’s original prompt; it asks which behavioral principles remain useful after stripping Claude‑specific implementation details, yielding a portable prompt set.

Contributing – Issues and pull requests are welcome for generalizing vendor‑specific bits, simplifying redundancies, or improving cross‑model compatibility.