{
  "id": "pythia-410m",
  "name": "pythia-410m",
  "identifiers": {
    "huggingface": [
      "EleutherAI/pythia-410m"
    ]
  },
  "developer": "EleutherAI",
  "release_date": {
    "value": "2023-02-13",
    "source": "https://huggingface.co/api/models/EleutherAI/pythia-410m",
    "status": "partial",
    "note": "HF repo creation date; may predate or postdate public release."
  },
  "weights_status": "open",
  "availability": {
    "value": "available",
    "checked": "2026-09-24",
    "source": "https://huggingface.co/EleutherAI/pythia-410m"
  },
  "license": {
    "value": "apache-2.0",
    "source": "https://huggingface.co/EleutherAI/pythia-410m/blob/9879c9b5f8bea9051dcb0e68dff21493d67e9d4f/README.md",
    "status": "partial",
    "note": "From HF card metadata (uploader-declared); confirm against the license text."
  },
  "architecture": {
    "family": "decoder_only",
    "note": "family read from config 'architectures': ['GPTNeoXForCausalLM'].",
    "n_layers": {
      "value": 24,
      "source": "https://huggingface.co/EleutherAI/pythia-410m/raw/9879c9b5f8bea9051dcb0e68dff21493d67e9d4f/config.json",
      "status": "recorded"
    },
    "hidden_size": {
      "value": 1024,
      "source": "https://huggingface.co/EleutherAI/pythia-410m/raw/9879c9b5f8bea9051dcb0e68dff21493d67e9d4f/config.json",
      "status": "recorded"
    },
    "n_heads": {
      "value": 16,
      "source": "https://huggingface.co/EleutherAI/pythia-410m/raw/9879c9b5f8bea9051dcb0e68dff21493d67e9d4f/config.json",
      "status": "recorded"
    },
    "vocab_size": {
      "value": 50304,
      "source": "https://huggingface.co/EleutherAI/pythia-410m/raw/9879c9b5f8bea9051dcb0e68dff21493d67e9d4f/config.json",
      "status": "recorded"
    },
    "context_length": {
      "value": 2048,
      "source": "https://huggingface.co/EleutherAI/pythia-410m/raw/9879c9b5f8bea9051dcb0e68dff21493d67e9d4f/config.json",
      "status": "recorded"
    },
    "positional_encoding": {
      "value": "rotary (RoPE), partial: 25% of dims",
      "source": "https://arxiv.org/abs/2304.01373",
      "status": "recorded",
      "note": "Paper sec 2.3: 'We use rotary embeddings'; fraction is config rotary_pct 0.25. Same as pythia-6-9b."
    }
  },
  "training_data": {
    "value": "The Pile (300B tokens). One of 8 sizes trained on identical data in identical order (Pythia paper).",
    "source": "https://arxiv.org/abs/2304.01373",
    "status": "recorded"
  },
  "techniques": [],
  "primary_sources": [
    "https://huggingface.co/EleutherAI/pythia-410m",
    "https://huggingface.co/EleutherAI/pythia-410m/raw/9879c9b5f8bea9051dcb0e68dff21493d67e9d4f/config.json"
  ],
  "record_history": [
    {
      "date": "2026-09-24",
      "change": "ingested as candidate from HF (EleutherAI/pythia-410m@9879c9b5f8bea9051dcb0e68dff21493d67e9d4f)",
      "by": "ingest_hf.py"
    },
    {
      "date": "2026-09-24",
      "change": "preparer: developer, positional encoding set; trained_on accepted",
      "by": "claude (preparer, Sonnet 5)"
    },
    {
      "date": "2026-09-24",
      "change": "preparer cleanup: removed 3 stale flag(s), filled training_data",
      "by": "claude (preparer, Sonnet 5)"
    },
    {
      "date": "2026-09-24",
      "change": "reviewed and promoted from staging (1 edge(s) accepted)",
      "by": "Wilson Pruitt"
    }
  ]
}