Model reference · open weights

circu-sparsity

Available as managed deployment LLMs openai Text gen 1 variants 465 dl/mo

circu-sparsity is an open-weight language model from openai. AxForge deploys and operates it for you on dedicated EU-owned hardware — with the licence handled where one is required.

Available as managed deployment — configured and operated for you on dedicated EU hardware, quoted per deployment.

What it is

Makeropenai
TypeLanguage models
TaskText gen
Parameters (lead)419M
Runs withtransformers
Released2025-12-11
Popularity465 downloads / month
LicenceOpen weights

About

What circu-sparsity is

Sparse Model from Gao et al. 2025

Weights for a sparse model from Gao et al. 2025, used for the qualitative results from the paper (related to bracket counting and variable binding). All weights for the other models used in the paper, as well as lightweight inference code, are present in https://github.com/openai/circuit_sparsity. In the context of that repo, this model is csp_yolo2.

This is a runnable standalone huggingface implementation for one of the models. It includes code to load the locally converted HF model + tokenizer and run a tiny generation.

import torch
from transformers import AutoModelForCausalLM, AutoTokenizer

if __name__ == "__main__":
    PROMPT = "def square_sum(xs):\n    return sum(x * x for x in xs)\n\nsquare_sum([1, 2, 3])\n"
    tok = AutoTokenizer.from_pretrained("openai/circuit-sparsity", trust_remote_code=True)
    model = AutoModelForCausalLM.from_pretrained(
        "openai/circuit-sparsity",
        trust_remote_code=True,
        torch_dtype="auto",
    )
    model.to("cuda" if torch.cuda.is_available() else "cpu")
    inputs = tok(PROMPT, return_tensors="pt", add_special_tokens=False)["input_ids"].to(
        model.device
    )

    with torch.no_grad():
        out = model.generate(
            inputs,
            max_new_tokens=64,
            do_sample=True,
            temperature=0.8,
            top_p=0.95,
            return_dict_in_generate=False,
        )

    print("=== Prompt ===")
    print(PROMPT)
    print("\n=== Generation ===")
    print(tok.decode(out[0], skip_special_tokens=True))

License

This project is licensed under the Apache License 2.0.

From the published model card. Full card on the HuggingFace links in the sidebar.

Using it via the API

Call it like any OpenAI endpoint

Once AxForge deploys circu-sparsity for you, it answers on the OpenAI-compatible API — the same base URL and keys as every other model. (circu-sparsity below is illustrative; you get the exact model name on deployment.)

$ curl -sS https://api.axforge.ai/v1/chat/completions \
  -H "Authorization: Bearer $AXFORGE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"circu-sparsity","messages":[{"role":"user","content":"Hello"}]}'

Create an account — your API key is available in the console. 5M tokens/month currently included with every new account at launch.

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