---
language:
- en
license: apache-2.0
library_name: transformers
base_model:
  - mistralai/Mistral-Nemo-Base-2407   # lightweight student
  - Qwen/Qwen3-235B-A22B              # thinking + non-thinking teacher
tags:
- distillation
- /think
- /nothink
- reasoning-transfer
- arcee-ai
---

![Homunculus Logo](https://huggingface.co/arcee-ai/Homunculus/resolve/main/logo.jpg)

# Arcee **Homunculus-12B**

**Homunculus** is a 12 billion-parameter instruction model distilled from **Qwen3-235B** onto the **Mistral-Nemo** backbone.
It was purpose-built to preserve Qwen’s two-mode interaction style—`/think` (deliberate chain-of-thought) and `/nothink` (concise answers)—while running on a single consumer GPU.

---

## ✨ What’s special?

| Feature                           | Detail                                                                                                                                               |
| --------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------- |
| **Reasoning-trace transfer**      | Instead of copying just final probabilities, we align *full* logit trajectories, yielding more faithful reasoning.        |
| **Total-Variation-Distance loss** | To better match the teacher’s confidence distribution and smooth the loss landscape. |
| **Tokenizer replacement**         | The original Mistral tokenizer was swapped for Qwen3's tokenizer.                          |
| **Dual interaction modes**        | Use `/think` when you want transparent step-by-step reasoning (good for analysis & debugging). Use `/nothink` for terse, production-ready answers. Most reliable in the system role field.   |                    |

---

## Benchmark results

| Benchmark | Score |
| --------- | ----- |
| GPQADiamond (average of 3) | 57.1% |
| mmlu | 67.5% |

## 🔧 Quick Start

```python
from transformers import AutoTokenizer, AutoModelForCausalLM

model_id = "arcee-ai/Homunculus"
tokenizer = AutoTokenizer.from_pretrained(model_id)
model = AutoModelForCausalLM.from_pretrained(
    model_id, 
    torch_dtype="auto",
    device_map="auto"
)

# /think mode - Chain-of-thought reasoning
messages = [
    {"role": "system", "content": "You are a helpful assistant. /think"},
    {"role": "user", "content": "Why is the sky blue?"},
]
output = model.generate(
    tokenizer.apply_chat_template(messages, tokenize=True, return_tensors="pt"),
    max_new_tokens=512,
    temperature=0.7
)
print(tokenizer.decode(output[0], skip_special_tokens=True))

# /nothink mode - Direct answers
messages = [
    {"role": "system", "content": "You are a helpful assistant. /nothink"},
    {"role": "user", "content": "Summarize the plot of Hamlet in two sentences."},
]
output = model.generate(
    tokenizer.apply_chat_template(messages, tokenize=True, return_tensors="pt"),
    max_new_tokens=128,
    temperature=0.7
)
print(tokenizer.decode(output[0], skip_special_tokens=True))
```

## 💡 Intended Use & Limitations

Homunculus is designed for:

* **Research** on reasoning-trace distillation, Logit Imitation, and mode-switchable assistants.
* **Lightweight production** deployments that need strong reasoning at <12 GB VRAM.

### Known limitations

* May inherit biases from the Qwen3 teacher and internet-scale pretraining data.
* Long-context (>32 k tokens) use is experimental—expect latency & memory overhead.

---