---
license: other
license_name: prism-research
license_link: LICENSE.md
language:
- en
- zh
tags:
- stepfun
- prism
- moe
- reasoning
- coding
- agentic
- abliterated
pipeline_tag: text-generation
library_name: transformers
base_model:
- stepfun-ai/Step-3.5-Flash
base_model_relation: finetune
---

[![Parameters](https://img.shields.io/badge/Parameters-196B_(11B_Active)-blue)]()
[![Architecture](https://img.shields.io/badge/Architecture-MoE-green)]()
[![Context](https://img.shields.io/badge/Context-256K-orange)]()
[![MTP](https://img.shields.io/badge/MTP--3-350_tok%2Fs_Peak-purple)]()


<p align="center">
  <img src="https://cdn-uploads.huggingface.co/production/uploads/63adf1fa42fd3b8dbaeb0c92/NkmQvQUXzckiRb8U__203.png" width="400"/>
</p>

# Step-3.5-Flash-PRISM

A "role-play" following unrestricted/unchained PRISM-LITE version of [StepFun's Step 3.5 Flash](https://huggingface.co/stepfun-ai/Step-3.5-Flash) intended particularly for over-refusal and propaganda mechanisms suppression using our SOTA PRISM pipeline. 

For Full Custom Production PRISM versions & tensors reach out.
<div align="center">

### ☕ Support Our Work

If you enjoy our work and find it useful, please consider sponsoring or supporting us!

[![Ko-fi](https://img.shields.io/badge/Ko--fi-Support%20Us-ff5e5b?logo=ko-fi&logoColor=white)](https://ko-fi.com/ericelbaz)

| Option | Description |
|--------|-------------|
| [**PRISM VIP Membership**](https://ko-fi.com/summary/6bae206c-a751-4868-8dc7-f531afd1fb4c) | Access to all PRISM models |
| **Bitcoin** | `bc1qarq2pyn4psjpcxzp2ghgwaq6y2h4e53q232x8r` |

![image](https://cdn-uploads.huggingface.co/production/uploads/63adf1fa42fd3b8dbaeb0c92/Psgbl1TgyDok__C7AMQog.png)

</div>

---

## Model Highlights

- **PRISM Ablation** — State-of-the-art technique that removes over-refusal behaviors while preserving model capabilities
- **196B MoE Architecture** — 196 billion total parameters with only 11 billion active per token across 288 fine-grained routed experts + 1 shared expert
- **Multi-Token Prediction (MTP-3)** — Predicts 4 tokens simultaneously, achieving 100–300 tok/s typical throughput (peaking at 350 tok/s)
- **256K Context Window** — Cost-efficient long context via 3:1 Sliding Window Attention (SWA) ratio
- **Frontier Reasoning & Coding** — 97.3 on AIME 2025, 74.4% on SWE-bench Verified, 51.0% on Terminal-Bench 2.0
- **Accessible Local Deployment** — Runs on high-end consumer hardware (Mac Studio M4 Max, NVIDIA DGX Spark)

## Model Architecture

| Specification | Value |
|---------------|-------|
| Architecture | Sparse Mixture-of-Experts (MoE) |
| Backbone | 45-layer Transformer (4,096 hidden dim) |
| Total Parameters | 196.81B (196B Backbone + 0.81B Head) |
| Activated Parameters | ~11B (per token) |
| Routed Experts per Layer | 288 |
| Shared Experts | 1 (always active) |
| Selected Experts per Token | Top-8 |
| Vocabulary Size | 128,896 |
| Context Length | 256K |
| Attention | Hybrid SWA (3:1 SWA-to-Full ratio) |
| MTP Head | Sliding-window attention + dense FFN (4 tokens/pass) |

## Benchmarks

| Benchmark | Step 3.5 Flash | DeepSeek V3.2 | Kimi K2.5 | GLM-4.7 | MiniMax M2.1 |
|-----------|---------------|---------------|-----------|---------|--------------|
| **Agent** | | | | | |
| τ²-Bench | 88.2 | 80.3 | 85.4 | 87.4 | 86.6 |
| BrowseComp | 51.6 | 51.4 | 60.6 | 52.0 | 47.4 |
| GAIA (no file) | 84.5 | 75.1 | 75.9 | 61.9 | 64.3 |
| xbench-DeepSearch (2025.05) | 83.7 | 78.0 | 76.7 | 72.0 | 68.7 |
| **Reasoning** | | | | | |
| AIME 2025 | 97.3 | 93.1 | 96.1 | 95.7 | 83.0 |
| HMMT 2025 (Feb.) | 98.4 | 92.5 | 95.4 | 97.1 | 71.0 |
| IMOAnswerBench | 85.4 | 78.3 | 81.8 | 82.0 | 60.4 |
| **Coding** | | | | | |
| LiveCodeBench-V6 | 86.4 | 83.3 | 85.0 | 84.9 | — |
| SWE-bench Verified | 74.4 | 73.1 | 76.8 | 73.8 | 74.0 |
| Terminal-Bench 2.0 | 51.0 | 46.4 | 50.8 | 41.0 | 47.9 |


### llama.cpp (GGUF)

For local deployment (requires ~120 GB VRAM for int4, smaller quants are available):

```bash
./llama-cli -m step3.5_flash_prism_Q4_K_S.gguf --jinja
```

## Recommended Parameters

| Use Case | Temperature | Top-P | Max New Tokens |
|----------|-------------|-------|----------------|
| Reasoning / Coding | 1.0 | 0.95 | 32768 |
| General Chat | 0.6 | 0.95 | 4096 |

## Hardware Requirements

| Setup | Details |
|-------|---------|
| **BF16 (Full)** | 8x H100/A100 80GB with tensor parallelism |
| **FP8 Quantized** | 8x A100 80GB with expert parallelism |
| **GGUF INT4 (Local)** | ~120 GB unified memory (Mac Studio M4 Max 128GB, DGX Spark, AMD Ryzen AI Max+ 395) |

## License

This model is released under the [PRISM Research License](LICENSE.md).

## Acknowledgments

Based on [Step 3.5 Flash](https://huggingface.co/stepfun-ai/Step-3.5-Flash) by [StepFun AI](https://www.stepfun.com). See the [technical report](https://github.com/stepfun-ai/Step-3.5-Flash/blob/main/step_3p5_flash_tech_report.pdf) and [blog post](https://static.stepfun.com/blog/step-3.5-flash/) for more details on the base model.