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Holo4

Both Holo4 models ship in four precisions. Holo4 35B-A3B is under Apache 2.0; Holo4 27B is for research use. Recommended vLLM flags, on vLLM 0.28 or newer. Swap the repo and --served-model-name for the other size or precision.
Serves on port 8000, so the base URL is http://localhost:8000/v1. The rest of this page covers Holo3.1, with measured memory and speed.

Pick a size

Weights on disk are the minimum GPU or unified memory you need. The KV cache and the image encoder come on top. 35B-A3B is the model the API serves as holo3-1-35b-a3b, and the one to run quantized (next section). 9B and 4B are dense models that fit on a single GPU. 0.8B is for on-device use.

Pick a precision

35B-A3B also comes in three quantized checkpoints. NVFP4 needs a third of the memory of BF16. Throughput measured with vLLM’s benchmark tool on an agentic workload: 12k input tokens, 1k output tokens, three 1080p images per request, concurrency 1. NVFP4 uses NVIDIA Model Optimizer in a W4A16 configuration.

Agent speed

Token throughput matters less than how many steps the agent gets through in a minute. Holo3.1 35B-A3B inside HoloDesktop CLI, by hardware and precision: On DGX Spark, NVFP4 plus the harness optimizations cut the average step from 6.8 s to 3.3 s, about twice as fast as the FP8 baseline. The fast harness (holo run --fast) takes one screenshot per step, skips thinking, and sends smaller images. It is quicker and less accurate on fiddly UIs. llama.cpp does not yet cache prefixes or images for the Qwen architecture, which holds its throughput back.

Run it

1

Start a server

Use llama.cpp with Metal acceleration and the Q4_K_M GGUF weights. You want an M3 or newer with at least 36 GB of unified memory: the weights alone take 21 GB, and prefix caching needs room for the KV cache. If memory is tight, lower --cache-ram and --ctx-size.
Tuned flags for higher throughput:
Serves on port 8080, so the base URL is http://localhost:8080/v1. Any string works as the model ID.
2

Point your client at it

Same client as the Quickstart, different base_url. The server ignores the API key, but the OpenAI SDKs refuse an empty one.
For MCP and ACP hosts, see Local mode from hosts.

Next steps

Core concepts

The harness conventions Holo expects, hosted or local.

HoloDesktop CLI

A ready-made desktop agent that runs on your local server.