Model reference · open weights
LBS is an open-weight language model from inclusionAI. LBS-27B (BF16) weighs 54.7 GB; the smallest configuration that runs it is H100 80 GB.
For self-hosting, compare this build's requirements below with the GPU you plan to rent.
Summary of the inclusionAI/LBS-27B model card, 2026-10-27
What it is
| Released by | inclusionAI |
|---|---|
| Released | 2026-10-26 |
| Parameters | 3M |
| VRAM | 54.7 GB for the weights |
What it runs on
| Card | Requests at once | Context max | Memory | |
|---|---|---|---|---|
| 8K each | 32K each | |||
| RTX 3060 12 GB … L40S 48 GB 6 smaller cards | ||||
| A100 80 GB | 25 | 8 | all 256K | 78.2 GB |
| H100 80 GB | 18 | 6 | 227K | 78.1 GB |
| RTX PRO 6000 Blackwell 96 GB | 37 | 12 | all 256K | 93.8 GB |
| DGX Spark (GB10) 128 GB unified | 53 | 18 | all 256K | 107 GB |
| H200 141 GB | 89 | 30 | all 256K | 138 GB |
| B200 180 GB | 133 | 45 | all 256K | 176 GB |
| 2× L40S 48 GB tensor parallel | 34 | 11 | all 256K | 44.0 GB a card |
| 4× RTX 4090 24 GB tensor parallel | 35 | 12 | all 256K | 23.4 GB a card |
| 4× RTX 3090 24 GB tensor parallel | 35 | 12 | all 256K | 23.4 GB a card |
| 4× RTX 5090 32 GB tensor parallel | 71 | 24 | all 256K | 31.0 GB a card |
| Requests at once | 8K tokens each | 32K tokens each |
|---|---|---|
| 1 | 57.8 GB | 59.4 GB |
| 5 | 61.1 GB | 69.2 GB |
| 8 | 63.7 GB | 76.6 GB |
| 16 | 70.4 GB | 96.2 GB |
| 32 | 83.9 GB | 135 GB |
| 64 | 111 GB | 214 GB |
One card, with vLLM's small-card settings.
From the model card
Learning to Look Beyond Screens: Transferable Visual Observation from GUI Grounding
LBS-27B is an agentic vision-language model based on Qwen3.8-27b. It learns to select and inspect image regions through GUI grounding, then transfers this observation policy to general-domain visual question answering and high-resolution perception.
Training uses only synthetic GUI grounding data, with no general-domain data or VQA questions: approximately 10K cold-start SFT examples, followed by 80 GRPO steps with a batch size of 64 and 8 rollouts per prompt.
| Benchmark | Records | Metric | Score (%) |
|---|---|---|---|
| ScreenSpot-Pro | 1,581 | Action accuracy | 81.15 |
| OS-World-G (Refine) | 564 | Action accuracy, including refusal | 84.57 |
| PerceptionBench | 3,000 | Judge accuracy | 59.67 |
| HR-Bench 4K | 800 | Strict option matching | 89.13 |
| HR-Bench 8K | 800 | Strict option matching | 87.75 |
All LBS scores use agentic zoom-in over complete benchmark runs. PerceptionBench uses a self-hosted Deepseekv4-flash-0731 judge, with zero failed or skipped judgments; repeated judgments may vary. Chart references use different inference setups and GPT-oss-120B for PerceptionBench, so comparisons are not controlled. See comparison notes.
More result visualizations are available in the LBS project; we have not performed any additional fine-tuning on general-domain data and welcome further RL experiments in specific subdomains.
Serve the released checkpoint in a compatible vLLM environment. Adjust the four-device example below for your hardware:
git clone --branch LBS --single-branch https://github.com/inclusionAI/UI-Venus.git
cd UI-Venus/evaluation
bash scripts/serve_vllm.sh start inclusionAI/LBS-27B \
--name lbs --tp 4 --dp 1 --daemon
LBS emits plain-text crop_image actions. A client must execute the crops and
return the images and coordinate mappings for multi-turn inference. Final GUI
coordinates use [x.xx,y.yy], normalized to [0,1000] on the original image.
Grounding predicts a location; operating a live application requires a separate
executor.
The evaluation guide
provides the client and benchmark setup. Configure endpoints and credentials in
an ignored .env.run copied from .env.example, using the actual model ID from
/v1/models. Wrappers default to reasoning_effort=xhigh and
thinking_budget=4096 through chat_template_kwargs; direct Python entries can
default to high.
The model weights and project software are released under Apache 2.0. Third-party datasets and screenshots retain their original licenses and terms.
Quoted from the model card on Hugging Face. The full card is behind the Hugging Face link above.