AX Gemma 4 12B IT MLX 6-bit Assistant MTP

Parameter count: approximately 11.96B logical target parameters (12B class). 6-bit is the target quantization precision, not a 6B model-size claim. The separately packaged assistant is an acceleration component and is not included in the target count.

This is a self-contained MLX model package for Apple Silicon. It combines the Gemma 4 12B instruction-tuned target with its exact paired assistant model for AX Engine multi-token prediction (MTP) / speculative decoding.

The target model verifies every drafted token. The assistant improves decode speed without replacing the target model or changing its output distribution. This repository does not contain PyTorch or GGUF target weights.

Model details

  • Base model: google/gemma-4-12B-it
  • MLX target: mlx-community/gemma-4-12B-it-6bit, revision f0d6f5d34239a612f695362750044905e6dd072c
  • Assistant: mlx-community/gemma-4-12B-it-assistant-6bit, revision 69fe060358f645f9231ac9e67451c81794e56b42
  • Format: MLX Safetensors target plus an AX Engine assistant subtree
  • Target quantization: 6-bit affine, group size 64; FFN projections retain 8-bit overrides
  • Assistant quantization: 6-bit affine, group size 64
  • Configured context length: 131,072 tokens
  • MTP pairing: exact
  • Maximum packaged draft depth: 2
  • Intended hardware: Apple Silicon

The target weight shards and assistant weights are byte-identical to the pinned upstream revisions. AX Engine adds native manifests, an assistant pairing contract, an AX-compatible assistant configuration, and a target-tokenizer copy inside assistant/.

Download

hf download AutomatosX/AX-Gemma-4-12B-IT-MLX-6bit-Assistant-MTP \
  --local-dir ./AX-Gemma-4-12B-IT-MLX-6bit-Assistant-MTP

The repository is approximately 12.3 GB. Ensure that the destination has enough free space before downloading.

Use with AX Engine MTP

Install AX Engine, then serve the downloaded repository directory:

ax-engine serve ./AX-Gemma-4-12B-IT-MLX-6bit-Assistant-MTP --port 31418

Gemma assistant MTP is enabled by default. AX Engine reads ax_gemma4_assistant_mtp.json, loads the compact drafter from assistant/, and uses the 12B target to verify proposals. Do not load assistant/ by itself as a general-purpose chat model.

The target weights can also be used for direct MLX generation, but the nested assistant acceleration and pairing contract are AX Engine-specific.

Package layout

  • model-*.safetensors: 6-bit MLX target weights
  • model.safetensors.index.json: target shard index
  • assistant/model.safetensors: paired 6-bit assistant weights
  • model-manifest.json and assistant/model-manifest.json: AX native manifests
  • ax_gemma4_assistant_mtp.json: exact-pairing and draft-depth contract
  • ax_provenance.json: pinned sources and checksums

Validation and provenance

Validated on macOS arm64 with AX Engine 6.9.0 on 2026-07-20:

  • AX native artifact validation: ready, with no issues
  • All target weight shards: byte-exact against the pinned MLX source
  • Assistant weight: byte-exact against the pinned assistant source
  • Assistant and target tokenizer: byte-identical inside the package
  • Pairing contract: exact
  • Canonical chat template: pinned from Google Gemma 4 and applied to the target

See ax_provenance.json for immutable source revisions and SHA-256 values.

License

Apache License 2.0. Review the Gemma terms and the original Google model cards for usage limitations and responsible-use guidance.

Downloads last month
145
Safetensors
Model size
12B params
Tensor type
BF16
·
U32
·
MLX
Hardware compatibility
Log In to add your hardware

6-bit

Inference Providers NEW
This model isn't deployed by any Inference Provider. 🙋 Ask for provider support

Model tree for AutomatosX/AX-Gemma-4-12B-IT-MLX-6bit-Assistant-MTP

Quantized
(282)
this model

Collection including AutomatosX/AX-Gemma-4-12B-IT-MLX-6bit-Assistant-MTP