---

pipeline_tag: text-generation

base_model:

• Spark-X2.5-4B

license: apache-2.0

license_name: apache-2.0

library_name: llama-cpp

tags:

• spark-x2.5
• 4b
• text-generation
• gguf
• quantized
• reasoning

languages:

• en
• zh

---

Spark-X2.5-4B GGUF

GGUF quantized versions of XHToken/Spark-X2.5-4B, a reasoning-capable language model designed for efficient deployment.

Model Overview

Spark-X2.5-4B is a high-performance 4B parameter model specializing in reasoning and text generation. It supports a thinking/reasoning mode where the model generates a chain-of-thought process before providing the final answer, allowing for more accurate and complex problem solving.

The model utilizes a structured conversation format with role-based delimiters (<|System|>, <|User|>, <|Bot|>) and explicitly handles reasoning via <think> blocks.

Model Architecture

| Property | Value |

| :---------------------- | :---------- |

| Architecture | Transformer |

| Parameters | 4B |

| Supported Languages | en, zh |

Available GGUF Files

| File | Quantization | Use Case |

| :-------------------------- | :----------- | :--------------------------------- |

| spark-x2.5-4b-nvfp4.gguf | NVFP4 | Optimized 4-bit quantization |

Usage

llama.cpp CLI

./llama-cli \
  -m spark-x2.5-4b-nvfp4.gguf \
  -p "Explain quantum computing in simple terms." \
  --temp 1.0 --top-p 0.95 --top-k 20

llama-server (OpenAI-compatible API)

./llama-server \
  -m spark-x2.5-4b-nvfp4.gguf \
  --host [IP_ADDRESS] --port 8080

Thinking Mode

Thinking mode is integrated into the model's output. The model generates its internal reasoning process within <think> and </think> tags before providing the final answer. This behavior can be controlled via the enable_thinking parameter in the chat template.

Tool Calling

The model supports structured tool calling. Tool definitions are provided in the system prompt, and the model responds using <tool_call> blocks with specific argument tags, which are then processed and returned via tool response tags.

Generation Parameters

Recommended parameters for optimal performance:

| Parameter | Value |

| :---------- | :---- |

| Temperature | 1.0 |

| Top-P | 0.95 |

| Top-K | 20 |

Quantization

These GGUF files were created from the source model using llama-quantize from the llama.cpp project.

Acknowledgements

• Original model: XHToken/Spark-X2.5-4B
• Quantization tool: llama.cpp

License

Apache License 2.0