arcee-ai / Homunculus

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?

Benchmark results

🔧 Quick Start

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.