Model reference · open weights

opt

opt is an open-weight language model from facebook, listed in the AxForge catalogue. AxForge can bring it up on EU-owned hardware for you on request — with the licence handled where one is required.

Licence fee required LLMs facebook 1 variants 11.4M downloads/mo
Request a licence + hosting quote All served models Not on the shared API today — deployed on request.

About

What opt is

OPT : Open Pre-trained Transformer Language Models OPT was first introduced in Open Pre-trained Transformer Language Models and first released in metaseq's repository on May 3rd 2022 by Meta AI. Disclaimer: The team releasing OPT wrote an official model card, which is available in Appendix D of the paper. Content from this model card has been written by the Hugging Face team. Intro To quote the first two paragraphs of the official paper Large language models trained on massive text collections have shown surprising emergent capabilities to generate text and perform zero- and few-shot learning. While in some cases the public can interact with these models through paid APIs, full model access is currently limited to only a few highly resourced labs. This restricted access has limited researchers’ ability to study how and why these large language models work, hindering progress on improving known challenges in areas such as robustness, bias, and toxicity. We present Open Pretrained Transformers (OPT), a suite of decoder-only pre-trained transformers ranging from 125M to 175B parameters, which we aim to fully and responsibly share with interested researchers. We train the OPT models to roughly match the performance and sizes of the GPT-3 class of models, while also applying the latest best practices in data collection and efficient training. Our aim in developing this suite of OPT models is to enable reproducible and responsible research at scale, and to bring more voices to the table in studying the impact of these LLMs. Definitions of risk, harm, bias, and toxicity, etc., should be articulated by the collective research community as a whole, which is only possible when models are available for study. Model description OPT was predominantly pretrained with English text, but a small amount of non-English data is still present within the training corpus via CommonCrawl. The model was pretrained using a causal language modeling (CLM) objective. OPT belongs to the same family of decoder-only models like GPT-3. As such, it was pretrained using the self-supervised causal language modedling objective. For evaluation, OPT follows GPT-3 by using their prompts and overall ex

Summarised from the published model card. Read the full card on the HuggingFace links below.

Specifications

What it is

Makerfacebook
TypeLanguage models
Variants1
Runs withtransformers
Released2022-05-11
Popularity11.4M downloads / month
Likes294
LicenceCommercial licence needed

How it works

How language models work

Your prompttext / messagesTransformerattention over tokensNext-token loopgenerate + streamResponsetext · tool callsA language model reads your tokens and predicts the next one, again and again, streaming the reply back.

Variants

Sizes & precisions

Open weights ship in several sizes and precisions. One page, all the variants — pick the one that fits your GPU. VRAM figures are estimates from model size.

VariantParamsPrecisionVRAMFits 16 GBWeights
opt-125mBF16Weights ↗

Using it via the API

Call it like any OpenAI endpoint

Once AxForge deploys opt for you, it answers on the OpenAI-compatible API — the same base URL and keys as every other model. (opt 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":"opt","messages":[{"role":"user","content":"Hello"}]}'

Details

Languages, data & research

Languages

en

Tags

transformers pytorch tf jax opt text-generation en text-generation-inference deploy:azure

Papers

Licence

Commercial licence needed

The weights are open but its licence needs a commercial agreement for business use. AxForge can arrange that licence and host the model for you — you pay AxForge, we settle with the model’s maker. Ask us for a quote. Read the licence ↗

Sources

Weights & code

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