Nib 4B (preview), FP8

FP8 weights of Nib 4B, in the same 128×128 block layout as Qwen's official FP8 releases (e4m3 weights, BF16 block scales, dynamic activations), with clipping calibrated on in-domain agent episodes including screenshots. 5.8 GB.

Only the main linear projections are quantized. The vision encoder, embeddings and tied output head, all norms, the Gated DeltaNet gates, convolutions and decay parameters, and the MTP weights are kept byte-for-byte from the BF16 model (in nib-protected.safetensors).

Mean KL vs BF16 p99 KL Top-1 agreement Browser tasks (581-task live set, paired)
FP8 0.0028 0.033 98.9% 42.5% vs 45.3% for BF16 (−2.8, 95% CI −6.4 to +1.0)

Fidelity is measured against the BF16 model on 5,070 held-out assistant tokens from 48 complete agent episodes (up to 32k tokens, ten harnesses), none used for calibration. The functional difference is within run-to-run noise: the NVFP4 build, with 5× this KL, scored 45.6% on the same tasks.

Serving (tested: SGLang 0.5.21)

python -m sglang.launch_server \
  --model-path ProCreations/nib-4b-preview-FP8 --served-model-name nib-4b \
  --context-length 131072 --reasoning-parser qwen3 --tool-call-parser qwen3_coder \
  --mamba-ssm-dtype bfloat16 --mamba-radix-cache-strategy extra_buffer_lazy --trust-remote-code

Tested on an RTX PRO 6000 (Blackwell) with CUDA graphs, radix cache and 8 concurrent requests.

Reasoning effort

Same as Nib 4B: pass chat_template_kwargs {"enable_thinking": false} for thinking off, or {"enable_thinking": true, "reasoning_effort": "low" | "medium" | "xhigh"} (xhigh is the default). All our evaluations used temperature 1.0 and top_p 0.95.

About Nib

Nib is Qwen3.5-4B post-trained as a browser agent across common agent harnesses. Benchmarks, usage, training details and limitations (including that it often reports success on tasks it did not finish) are on the main model card. This is a preview release.

License: Apache 2.0, the same as the base model Qwen/Qwen3.5-4B.

Downloads last month
-
Safetensors
Model size
5B params
Tensor type
F8_E4M3
·
F32
·
BF16
·
Inference Providers NEW
This model isn't deployed by any Inference Provider. 🙋 Ask for provider support

Model tree for ProCreations/nib-4b-preview-FP8

Finetuned
Qwen/Qwen3.5-4B
Quantized
(3)
this model