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John Hallman

Named behind 2 listings on Anchor Terminal.

Credited gpt-oss contributor; post-training researcher

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What John builds

  • gpt-oss-120b BB · Open-weight models

    gpt-oss-120b is OpenAI's open-weight mixture-of-experts reasoning model, 116.8B parameters with 5.1B active and a 131,072-token context, published on Hugging Face in MXFP4 under Apache 2.0.

    Credited gpt-oss contributor; post-training researcher, researched 26 October 2026 · the people behind it

  • gpt-oss-20b B · Open-weight models

    gpt-oss-20b is OpenAI's open-weight mixture-of-experts reasoning model, 21B parameters with 3.6B active and a 131,072-token context, published on Hugging Face in MXFP4 under Apache 2.0 and trained on the harmony prompt format.

    Credited gpt-oss contributor; post-training researcher, researched 26 October 2026 · the people behind it

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Questions

Who is John Hallman?

John Hallman is credited gpt-oss contributor; post-training researcher.

What does OpenAI make?

Anchor Terminal lists gpt-oss-120b and gpt-oss-20b from OpenAI. gpt-oss-120b is OpenAI's open-weight mixture-of-experts reasoning model, 116.8B parameters with 5.1B active and a 131,072-token context, published on Hugging Face in MXFP4 under Apache 2.0.

How are John's tools graded?

gpt-oss-120b is graded BB, 70.2 out of 100; gpt-oss-20b is graded B, 69.9 out of 100, on Anchor Terminal's benchmark, which scores every listing against the same checklist.

Sources (9)

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