Qwen2.5-1.5B-Instruct-heretic

A decensored variant of Qwen/Qwen2.5-1.5B-Instruct, produced with Heretic v1.2.0 (directional ablation / "abliteration"). Refusal behavior is suppressed via targeted weight edits to the attention output and MLP down-projections rather than fine-tuning, so the base model's knowledge and instruction-following are left largely intact.

Who this is for: developers who want a small Qwen2.5 model that answers directly instead of refusing — for local agents, roleplay, research on alignment/refusal mechanics, or any use case blocked by RLHF-era over-refusal. At 1.5B parameters it runs comfortably on CPU or low-VRAM GPUs while still outperforming the 0.5B variant on reasoning and coherence.

Abliteration parameters

Parameter Value
direction_index 18.83
attn.o_proj.max_weight 1.30
attn.o_proj.max_weight_position 20.35
attn.o_proj.min_weight 1.25
attn.o_proj.min_weight_distance 14.52
mlp.down_proj.max_weight 1.16
mlp.down_proj.max_weight_position 16.23
mlp.down_proj.min_weight 0.73
mlp.down_proj.min_weight_distance 8.56

Performance

Metric This model Original model (Qwen/Qwen2.5-1.5B-Instruct)
KL divergence 0.1607 0 (by definition)
Refusals 1/100 99/100

KL divergence of 0.16 on the output distribution is low — the edit is narrow and targeted rather than a broad perturbation. Refusals dropped from 99 to 1 out of 100 adversarial prompts, meaning the model complies while retaining nearly all of its original capabilities.

Made with ❤️ by RACER IS OP — follow for more uncensored models

Files

File Format Size
model.safetensors BF16 3.09 GB
Qwen2.5-1.5B-Instruct-heretic-Q8_0.gguf GGUF, Q8_0 1.65 GB
Qwen2.5-1.5B-Instruct-heretic-Q5_K_M.gguf GGUF, Q5_K_M 1.13 GB
Qwen2.5-1.5B-Instruct-heretic-Q4_K_M.gguf GGUF, Q4_K_M 986 MB

Quickstart

# llama.cpp
llama serve -hf saidutta69/Qwen2.5-1.5B-Instruct-heretic
# transformers
from transformers import AutoModelForCausalLM, AutoTokenizer

model_name = "saidutta69/Qwen2.5-1.5B-Instruct-heretic"
model = AutoModelForCausalLM.from_pretrained(model_name, torch_dtype="auto", device_map="auto")
tokenizer = AutoTokenizer.from_pretrained(model_name)

messages = [{"role": "user", "content": "Who are you?"}]
inputs = tokenizer.apply_chat_template(messages, add_generation_prompt=True, tokenize=True,
                                        return_dict=True, return_tensors="pt").to(model.device)
out = model.generate(**inputs, max_new_tokens=200)
print(tokenizer.decode(out[0][inputs["input_ids"].shape[-1]:], skip_special_tokens=True))

Also runnable via Ollama, LM Studio, Jan, vLLM, SGLang.

Responsible use

Refusal suppression is deliberate and works as intended: this model will comply with requests the base model would refuse, including some it shouldn't. There is no safety filtering layered on top. You are responsible for how you deploy it — don't put this behind an unmoderated public-facing endpoint serving third parties. It inherits Qwen2.5-1.5B-Instruct's factual limitations and biases; abliteration removes refusal directions, it doesn't add capability or judgment.

License

Inherits the Apache 2.0 license from the base model.

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