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Open-Source LLM · RedHatAI

gpt-oss-20b-speculator.eagle3

This is a speculator model (854M parameters) designed to accelerate inference of openai/gpt-oss-20b using EAGLE-3 speculative decoding. It predicts multiple future tokens to reduce latency. It's not a standalone model—it requires the 20B verifier model and compatible serving infrastructure (vLLM). Apache-2.0 licensed and ungated.

Source: HuggingFace — huggingface.co/RedHatAI/gpt-oss-20b-speculator.eagle3
855M
Parameters
apache-2.0
License (OSI-approved)
Unknown
Context (tokens)
40k
Downloads (30d)

Key facts

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

FieldValue
DeveloperRedHatAI
Parameters855M
Context windowUnknown
Licenseapache-2.0 — OSI-approved
Modality / tasktext-generation
Gated on HuggingFaceNo
Downloads40k
Likes11
Last updated2026-04-08
SourceRedHatAI/gpt-oss-20b-speculator.eagle3

What gpt-oss-20b-speculator.eagle3 is

A 854M-parameter Eagle3Speculator trained via distillation from openai/gpt-oss-120b hidden states using the speculators library. Accepts num_speculative_tokens (1–5) to trade off acceptance rate and speedup. Evaluated on seven use cases (coding, math, QA, RAG, summarization, translation) showing acceptance lengths of 1.5–2.75 tokens depending on k and task. Requires vLLM 0.17.1+ and compatible chat template integration with gpt-oss-20b.

Quickstart

Run gpt-oss-20b-speculator.eagle3 locally

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

quickstart.pypython
from transformers import pipelinepipe = pipeline("text-generation", model="RedHatAI/gpt-oss-20b-speculator.eagle3")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

High-throughput chat inference

Reduce latency on openai/gpt-oss-20b via speculative decoding; suitable for conversational APIs, customer support bots, and chat endpoints where token latency matters.

Coding and math reasoning acceleration

Empirical acceptance lengths 2.2–2.75 tokens on coding and math tasks; reduces per-token latency for IDE assistants and automated reasoning pipelines.

RAG and summarization workflows

Speculative decoding reduces generation time in long-context RAG and multi-turn summarization pipelines running on shared hardware.

Running & fine-tuning it

Estimate: 20B verifier + 854M speculator on single A100 (40 GB) or equivalent. Benchmark run used 1×A100 with vLLM 0.17.1 at batch size 128. For multi-GPU: tp=1 (tensor parallelism) indicated in example. Peak VRAM unknown; requires empirical profiling per batch size and num_speculative_tokens. FP16 or BF16 assumed but not explicitly stated.

Not applicable. This is a distilled speculator model trained on hidden states from gpt-oss-120b. Retraining or LoRA adaptation is not documented and likely not intended. Use case is fixed: acceleration of gpt-oss-20b inference.

When to avoid it — and what to weigh

  • Standalone inference required — This model is a speculator only; it cannot generate output independently. Must pair with openai/gpt-oss-20b verifier and compatible serving runtime.
  • Latency-insensitive workloads — If absolute throughput (tokens/sec) and cost are primary concerns over wall-clock latency, speculative decoding overhead may not justify the added complexity.
  • Single-GPU or resource-constrained deployment — Running both verifier (20B) and speculator (854M) requires sufficient VRAM; minimal hardware benefit on CPU-only or edge devices.
  • Non-vLLM serving infrastructure — Integration outside vLLM (e.g., llama.cpp, ONNX Runtime) is not documented; custom implementation required.

License & commercial use

Apache-2.0 (OSI-approved permissive license). No restrictions on use, modification, or distribution provided license text is retained.

Apache-2.0 permits commercial use without restriction. However, verify that the upstream verifier model (openai/gpt-oss-20b) and training datasets (Magpie-Llama-3.1-Pro, HuggingFaceH4/ultrachat) comply with your intended use case. The speculator itself poses no commercial-use barrier.

DEV.co evaluation signals

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

SignalAssessment
MaintenanceActive
DocumentationAdequate
License clarityClear
Deployment complexityModerate
DEV.co fitGood
Assessment confidenceHigh
Security considerations

Standard LLM considerations apply. Model is distilled from gpt-oss-120b; inherit any latent biases or vulnerabilities. Speculative decoding does not introduce new attack vectors but reduces visibility into token-level verification. Serve behind authenticated endpoints if handling sensitive data. No CVE or security audit data provided.

Alternatives to consider

Ollama with speculative decoding (if supported)

Simpler single-binary deployment; trade-off is less explicit control over speculative parameters and narrower model ecosystem.

TensorRT-LLM speculative plugin

Nvidia's inference optimization framework; may offer better throughput on H100/A100 but steeper integration overhead and proprietary CUDA dependency.

llama.cpp with custom speculator (not out-of-box)

If CPU inference is mandatory; requires manual speculative decoding implementation, not provided by this model.

Software development agency

Ship gpt-oss-20b-speculator.eagle3 with senior software developers

Integrate this speculator model with vLLM for real-time conversational AI and reasoning tasks. Contact our team to evaluate on your workload or request hosted endpoint configuration.

Talk to DEV.co

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gpt-oss-20b-speculator.eagle3 FAQ

Can I use this model without the openai/gpt-oss-20b verifier?
No. This is a speculator-only model designed specifically for acceleration of gpt-oss-20b. It cannot generate standalone output.
Is this model suitable for commercial AI applications?
The Apache-2.0 license permits commercial use of the speculator itself. However, verify that your use of the underlying verifier (gpt-oss-20b) and training datasets is compliant with their respective licenses and terms.
What GPU do I need to run this?
Benchmarks used 1×A100 (40 GB). For production, provision sufficient VRAM for both 20B verifier and 854M speculator, plus batch buffer. Exact VRAM requirement depends on batch size, sequence length, and quantization; empirical testing recommended.
Does speculative decoding always improve latency?
Not guaranteed. Speculative decoding reduces wall-clock latency per token, but adds computational overhead. Actual speedup depends on acceptance rate (shown in table per use case and k-value), batch size, and hardware. Math/coding show higher acceptance (2.2–2.75 tokens) than QA (1.5–1.93).

Custom software development services

From first prototype to production, DEV.co delivers software development services around tools like gpt-oss-20b-speculator.eagle3. Our software development agency staffs experienced software developers and web developers for custom software development, web development, integrations, and ongoing support across open-source llms and beyond.

Ready to deploy low-latency LLM inference?

Integrate this speculator model with vLLM for real-time conversational AI and reasoning tasks. Contact our team to evaluate on your workload or request hosted endpoint configuration.