By mrgoonie
Enforce a structured reasoning protocol that grounds claims in evidence, tests multiple hypotheses, runs concrete simulations, performs adversarial self-review, and delivers calibrated, outcome-first responses — useful for debugging, code review, analysis, and high-stakes writing.
The reasoning discipline of Claude Fable 5, distilled into an executable protocol — packaged as a Claude Code plugin.
→ View the live landing page · dark/light theme · EN / VI
Fable Thinking is not a persona to imitate. It is a set of mechanical procedures that make any model's reasoning more grounded, better calibrated, and harder to fool — including by its own fluent output. It cannot add capability; it removes the predictable failure modes that waste whatever capability the executing model has.
It works across models and runtimes (Claude, Codex/GPT, Gemini, local models).
Invoke when a task needs careful reasoning rather than a routine answer:
This repository is a Claude Code plugin marketplace. Add it, then install the plugin:
/plugin marketplace add mrgoonie/fable-thinking
/plugin install fable-thinking@fable-thinking
Or add the marketplace from its Git URL:
/plugin marketplace add https://github.com/mrgoonie/fable-thinking
After installing, the fable-thinking skill becomes available to Claude Code and is invoked automatically when a task calls for careful reasoning, or explicitly by name.
fable-thinking/
├── .claude-plugin/
│ ├── marketplace.json # Marketplace definition
│ └── plugin.json # Plugin manifest
├── skills/
│ └── fable-thinking/
│ ├── SKILL.md # The reasoning protocol
│ └── references/ # Content, design, and worked examples
├── web/ # Landing page (published to AgentWiki)
│ ├── index.html
│ └── assets/hero-dark.png
└── README.md
The landing page is published at api.agentwiki.cc/s/4pscSZumUfvoLT6jUUxz7 — dark/light theme, English and Vietnamese.
Distilled from the reasoning discipline of Claude Fable 5. Originally authored as part of AgentKit.
Based on adoption, maintenance, documentation, and repository signals. Not a security audit or endorsement.
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