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Open-Source LLM · prometheus-eval

prometheus-7b-v2.0

Prometheus 2 is a 7B-parameter language model fine-tuned on 300K human feedback examples to act as an automated evaluator for other LLMs. It specializes in both absolute grading (scoring responses 1-5) and relative grading (ranking two responses), making it useful as a cost-effective alternative to GPT-4 for evaluation tasks and RLHF reward modeling. Based on Mistral-7B-Instruct.

Source: HuggingFace — huggingface.co/prometheus-eval/prometheus-7b-v2.0
7.2B
Parameters
apache-2.0
License (OSI-approved)
Unknown
Context (tokens)
35.6k
Downloads (30d)

Key facts

Objective fields from the source. Values we can't verify are shown as “Unknown” rather than guessed.

FieldValue
Developerprometheus-eval
Parameters7.2B
Context windowUnknown
Licenseapache-2.0 — OSI-approved
Modality / tasktext-generation
Gated on HuggingFaceNo
Downloads35.6k
Likes109
Last updated2024-11-29
Sourceprometheus-eval/prometheus-7b-v2.0

What prometheus-7b-v2.0 is

Prometheus-7b-v2.0 is a Mistral-7B-Instruct derivative with 7.2B parameters, fine-tuned via supervised learning on curated feedback datasets (100K absolute, 200K preference examples). Uses weight merging to support dual evaluation modes (direct assessment and pairwise ranking). Requires explicit prompt templating and Mistral conversation format. Apache 2.0 licensed, ungated, and compatible with standard text-generation inference stacks.

Quickstart

Run prometheus-7b-v2.0 locally

Load the open weights with 🤗 Transformers and generate — the same model, self-hosted.

quickstart.pypython
from transformers import pipelinepipe = pipeline("text-generation", model="prometheus-eval/prometheus-7b-v2.0")out = pipe("Explain retrieval-augmented generation in one sentence.",           max_new_tokens=128)print(out[0]["generated_text"])

Swap in vLLM or Ollama for production-grade serving. DEV.co can stand up the inference stack.

Deployment

How you'd run it

A typical self-hosted path — open weights, an inference server, your application.

DEV.co builds each layer — from GPU infrastructure to the application.

Best use cases

Automated LLM Evaluation Pipeline

Replace expensive GPT-4 API calls for scoring and ranking LLM outputs in evaluation loops, benchmarking, or continuous improvement workflows.

RLHF Reward Model

Use as a preference/reward model in reinforcement learning from human feedback pipelines to score candidate outputs during policy training.

Quality Assurance & Content Grading

Implement automated rubric-based grading and feedback generation for educational, customer-facing, or internal content at scale.

Running & fine-tuning it

ESTIMATE: ~14–16 GB VRAM (fp16) for full model inference; ~7–8 GB with 8-bit quantization. Batch inference and longer context windows will increase VRAM demand. Context length is unstated; verify against Mistral-7B baseline (typically 32K). Requires GPU compute for practical throughput.

Model is already fine-tuned on curated evaluation data. Further fine-tuning is possible via LoRA/QLoRA for domain-specific rubrics or custom evaluation criteria, though no official tooling or scripts are provided. Training data composition (100K + 200K examples) suggests moderate fine-tuning feasibility.

When to avoid it — and what to weigh

  • Multi-language Evaluation Required — Model is trained on English feedback only; no stated multilingual capability.
  • Real-time, Ultra-low-latency Scoring — 7B model requires inference infrastructure; not suitable for sub-100ms latency requirements without significant optimization effort.
  • Specialized Domain Evaluation — Training data composition and domain coverage are not detailed; may not generalize to highly specialized evaluation rubrics (e.g., scientific, legal, medical edge cases).
  • Evaluating Non-text Modalities — Text-only model; cannot evaluate images, audio, code execution, or multimodal outputs.

License & commercial use

Apache 2.0 license. Model card notes that Feedback Collection, Preference Collection, and Prometheus 2 are subject to OpenAI's Terms of Use for the generated/training data. This restriction on training data provenance requires review before production use.

Apache 2.0 is a permissive OSI-approved license allowing commercial use, modification, and redistribution. However, the model card explicitly states the training data is subject to OpenAI's Terms of Use. This creates potential friction: while the model weights themselves are Apache 2.0, the lineage and restrictions on the training data may impose additional obligations. Requires legal review before deploying in production commercial systems.

DEV.co evaluation signals

Editorial assessment — not user reviews. Directional, with an explicit confidence level.

SignalAssessment
MaintenanceActive
DocumentationAdequate
License clarityNeeds review
Deployment complexityModerate
DEV.co fitStrong
Assessment confidenceHigh
Security considerations

No security audit, penetration testing results, or adversarial robustness claims are stated. As a fine-tuned model inheriting from Mistral-7B-Instruct, it may be susceptible to prompt injection, jailbreaking, or adversarial evaluation inputs designed to manipulate scores. Use in untrusted input scenarios (e.g., adversarial scoring) requires testing and guardrails. Model card does not discuss data leakage, memorization, or inference-time filtering.

Alternatives to consider

GPT-4 / GPT-4o (OpenAI)

Proprietary, higher capability baseline; no infrastructure cost. Trade: higher per-call cost, no local control, vendor lock-in. Prometheus 2 targets cost reduction for at-scale evaluation.

Judge-LLM (Meta/Llama-based) or other eval models

Alternative open-source evaluators exist (e.g., fine-tuned Llama variants). Limited public data; Prometheus 2's 300K curated examples is a distinguishing factor.

In-house Rubric Engine + Custom Fine-tune

If evaluation rubrics are highly proprietary, rolling your own model on internal data avoids OpenAI ToS restrictions and tailors to exact requirements. Higher upfront effort.

Software development agency

Ship prometheus-7b-v2.0 with senior software developers

Prometheus 2 is a production-ready, open-source evaluator. Review the GitHub repository and paper to understand prompt formatting and integration requirements, then deploy on your infrastructure or via managed endpoints. Verify OpenAI ToS compliance with legal before commercial use.

Talk to DEV.co

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prometheus-7b-v2.0 FAQ

Can I use Prometheus 2 commercially?
The model weights are Apache 2.0 licensed (permissive). However, the training data is subject to OpenAI's Terms of Use, which may impose additional restrictions on commercial deployment. Review OpenAI's ToS and consult legal before production use.
What hardware do I need to run Prometheus 2?
Approximately 14–16 GB VRAM (fp16) for inference, or 7–8 GB with 8-bit quantization. A modern GPU (A100, L40S, RTX 4090, etc.) is recommended. Exact VRAM and context length depend on batch size and input length; benchmark with your target workload.
How do I integrate Prometheus 2 into my evaluation pipeline?
The model card provides explicit prompt templates for absolute and relative grading. The GitHub repository (https://github.com/prometheus-eval/prometheus-eval) offers wrapper functions and classes; using these is recommended. You will need to instantiate the Mistral conversation template and format inputs according to the specified schema.
Does Prometheus 2 support languages other than English?
No; the model is trained on English feedback only and is not stated to support multilingual evaluation.

Work with a software development agency

Need help beyond evaluating prometheus-7b-v2.0? DEV.co is a software development agency offering software development services and web development for teams of every size. Our software developers and web developers build custom software, web applications, APIs, and open-source llms integrations — and maintain them long-term.

Ready to Automate Your LLM Evaluation?

Prometheus 2 is a production-ready, open-source evaluator. Review the GitHub repository and paper to understand prompt formatting and integration requirements, then deploy on your infrastructure or via managed endpoints. Verify OpenAI ToS compliance with legal before commercial use.