feifeinoban/shell
🐚 Shell: A Metacognition-Driven Safety Framework for Domain-Specific LLMs
Uncover and mitigate implicit value risks in education, finance, management—and beyond 🔒 Model-agnostic · 🧠 Self-evolving rules · ⚡ Activation steering · 📉 90%+ jailbreak reduction
  
Shell is an open safety framework that empowers domain-specific LLMs to detect, reflect on, and correct implicit value misalignments—without retraining. Built on the MENTOR architecture, it combines metacognitive self-assessment, dynamic rule evolution, and activation steering to deliver robust, interpretable, and efficient alignment across specialized verticals.
📌 Abstract
While current LLM safety methods focus on explicit harms (e.g., hate speech, violence), they often miss domain-specific implicit risks—such as encouraging academic dishonesty in education, promoting reckless trading in finance, or normalizing toxic workplace culture in management.
We introduce Shell, a metacognition-driven self-evolution framework that:
- Enables LLMs to self-diagnose value misalignments via perspective-taking and consequence simulation.
- Builds a hybrid rule system: expert-defined static trees + self-evolved dynamic graphs.
- Enforces rules at inference time via activation steering, achieving strong safety with minimal compute.
Evaluated on 9,000 risk queries across education, finance, and management, Shell reduces average jailbreak rates by >90% on models including GPT-5, Qwen3, and Llama 3.1.
🎯 Core Challenges: Implicit Risks Are Everywhere
💡 These risks are not jailbreaks in the traditional sense—they appear benign but subtly erode domain-specific values.
🧠 Methodology: The MENTOR Architecture
Shell implements the MENTOR framework (see paper for full details):
1. Metacognitive Self-Assessment
LLMs evaluate their own outputs using:
- Perspective-taking: "How would a teacher/parent/regulator view this?"
- Consequential thinking: "What real-world harm could this cause?"
- Normative introspection: "Does this align with core domain ethics?"
This replaces labor-intensive human labeling with autonomous, human-aligned reflection.
2. Rule Evolution Cycle (REC)
- Static Rule Tree: Expert-curated, hierarchical rules (e.g.,
Education → Academic Integrity → No Plagiarism). - Dynamic Rule Graph: Automatically generated from successful self-corrections (e.g.,
<risk: essay outsourcing> → <rule: teach outlining instead>). - Rules evolve via dual clustering (by risk type & mitigation strategy), enabling precise retrieval.
3. Robust Rule Vectors (RV) via Activation Steering
- Generate steering vectors from contrasting compliant vs. non-compliant responses.
- At inference, add vectors to internal activations (e.g., Layer 18 of Llama 3.1) to guide behavior.
- No fine-tuning needed—works on closed-source models like GPT-5.

Figure: The MENTOR framework (from paper). Shell implements this full pipeline.
📊 Results: Strong, Efficient, Generalizable
Jailbreak Rate Reduction (3,000 queries per domain)
✅ Human evaluators prefer Shell-augmented responses 68% of the time for safety, appropriateness, and usefulness.
🚀 Try It / Use It
For Researchers
- Dataset: 9,000 implicit-risk queries across 3 domains → [HF Dataset Link]
- Code: Full implementation of REC + RV → [GitHub Link] (coming soon)
- Cite:
@article{shell2025,
title={Shell: A Metacognition-Driven Safety Framework for Domain-Specific LLMs},
author={Wu, Wen and Ying, Zhenyu and He, Liang and Team, Shell},
journal={Anonymous Submission},
year={2025}
}