{
 "schema_version": "1.7.0",
 "id": "x_NXMC-2022-0003",
 "modified": "2026-10-19T02:33:38.839Z",
 "published": "2026-10-18T09:00:52.565Z",
 "summary": "t5-base: structural change at a4986ab (2022-12-12)",
 "details": "t5-base: architectures [\"T5WithLMHeadModel\"] to [\"T5ForConditionalGeneration\"]; a different class is instantiated from the same id (2022-12-12).\n\nRepository: https://huggingface.co/google-t5/t5-base. Revisions from a4986abc64c580966eb8dd0ed61ceafaeb0d1d45 onward carry this change; a pin at c1852398fbcceb89cd42afc33599f1edf42f3daa or earlier does not.\n\nChanged keys:\n- architectures: [\"T5WithLMHeadModel\"] -> [\"T5ForConditionalGeneration\"] (structural)\n\nThis record says what the change does mechanically. It is not a report that anything broke for anyone.",
 "affected": [
  {
   "ranges": [
    {
     "type": "GIT",
     "repo": "https://huggingface.co/google-t5/t5-base",
     "events": [
      {
       "introduced": "a4986abc64c580966eb8dd0ed61ceafaeb0d1d45"
      }
     ]
    }
   ],
   "database_specific": {
    "model": "google-t5/t5-base",
    "previous_revision": "c1852398fbcceb89cd42afc33599f1edf42f3daa"
   }
  }
 ],
 "references": [
  {
   "type": "INTRODUCED",
   "url": "https://huggingface.co/google-t5/t5-base/commit/a4986abc64c580966eb8dd0ed61ceafaeb0d1d45"
  },
  {
   "type": "PACKAGE",
   "url": "https://huggingface.co/google-t5/t5-base"
  },
  {
   "type": "WEB",
   "url": "https://www.neurarch.com/changes-feeds/models/google-t5/t5-base.html"
  }
 ],
 "database_specific": {
  "source": "neurarch model change tracker",
  "model": "google-t5/t5-base",
  "kind": "structural",
  "classes": [
   "structural"
  ],
  "changed_keys": [
   {
    "file": "config",
    "key": "architectures",
    "before": [
     "T5WithLMHeadModel"
    ],
    "after": [
     "T5ForConditionalGeneration"
    ],
    "class": "structural"
   }
  ],
  "impact": {
   "memory": false,
   "serving": true,
   "tokenizer": false,
   "licence": null
  },
  "breaking": true,
  "breaking_rule": "https://www.neurarch.com/changes-feeds/advisories/index.json#breaking_rule",
  "consequence": {
   "params": null,
   "weightsGbBf16": null,
   "trainPeakGb": null,
   "fingerprint": null,
   "context": null,
   "eos": null,
   "bos": null
  },
  "commit_date": "2022-12-12T16:09:56.000Z",
  "detected_at": "2026-10-18T09:00:52.565Z",
  "detected_by": "backfill",
  "days_since_first_commit": 1096,
  "license": "CC-BY-4.0"
 }
}