{
  "created_at": "2026-11-12T07:59:12Z",
  "result": {
    "engine": "context_compaction",
    "limits": "Checks the compaction record, not summary quality. It does not prove the must-retain list was complete or that the next decision uses the context correctly. The run is Ed25519-signed; pin the issuer key out of band.",
    "module": "cain_a75_engines/contextcompaction/engine.py",
    "profile": "retained_reasoning",
    "run": {
      "label": "Checks a context-compaction record: source binding, compression ratio, verbatim retention of every must-retain item, no critical drop, no invented item and claim honesty. It does not judge summary quality.",
      "public_key_b64": "LAcfWqEs+6ccdR9k4ywhsX8SkTERvA8PNtnYBJeoX/0=",
      "records": [
        {
          "checks": [
            {
              "detail": "the context hash covers exactly these items and their must-retain flags",
              "id": "binding.context_hash",
              "ok": true
            },
            {
              "detail": "2400 < 12000 tokens",
              "id": "compression.smaller",
              "ok": true
            },
            {
              "detail": "ratio 0.2 <= 0.3",
              "id": "compression.within_ratio",
              "ok": true
            },
            {
              "detail": "the retained id is in the source",
              "id": "retained.C-constraint.exists",
              "ok": true
            },
            {
              "detail": "the retained quote hashes to the source text",
              "id": "retained.C-constraint.verbatim",
              "ok": true
            },
            {
              "detail": "the retained id is in the source",
              "id": "retained.D-decision.exists",
              "ok": true
            },
            {
              "detail": "the retained quote hashes to the source text",
              "id": "retained.D-decision.verbatim",
              "ok": true
            },
            {
              "detail": "the retained id is in the source",
              "id": "retained.Q-open.exists",
              "ok": true
            },
            {
              "detail": "the retained quote hashes to the source text",
              "id": "retained.Q-open.verbatim",
              "ok": true
            },
            {
              "detail": "kept verbatim in the summary",
              "id": "C-constraint.must_retain_kept",
              "ok": true
            },
            {
              "detail": "not in the dropped list",
              "id": "C-constraint.must_retain_not_dropped",
              "ok": true
            },
            {
              "detail": "kept verbatim in the summary",
              "id": "D-decision.must_retain_kept",
              "ok": true
            },
            {
              "detail": "not in the dropped list",
              "id": "D-decision.must_retain_not_dropped",
              "ok": true
            },
            {
              "detail": "kept verbatim in the summary",
              "id": "Q-open.must_retain_kept",
              "ok": true
            },
            {
              "detail": "not in the dropped list",
              "id": "Q-open.must_retain_not_dropped",
              "ok": true
            },
            {
              "detail": "no invented item",
              "id": "retention.no_invented_items",
              "ok": true
            },
            {
              "detail": "claimed True, computed True",
              "id": "claims.all_critical_retained",
              "ok": true
            },
            {
              "detail": "claimed True, computed True",
              "id": "claims.compressed",
              "ok": true
            },
            {
              "detail": "claimed True, computed True",
              "id": "claims.no_invented_items",
              "ok": true
            }
          ],
          "created_at": "2026-11-12T07:59:12Z",
          "engine": "a75-015/1.0.0",
          "extra": {
            "computed": {
              "all_critical_retained": true,
              "compressed": true,
              "no_invented_items": true
            },
            "dropped": [
              "F-background"
            ],
            "ratio": 0.2,
            "retained": {
              "C-constraint": true,
              "D-decision": true,
              "Q-open": true
            }
          },
          "failed": [],
          "label": "Checks a context-compaction record: source binding, compression ratio, verbatim retention of every must-retain item, no critical drop, no invented item and claim honesty. It does not judge summary quality.",
          "prev_record_hash": "34d006eb36a0464115f895bd8a6b327f32b0d56a4166b52c653b751a314c8bba",
          "public_key_b64": "LAcfWqEs+6ccdR9k4ywhsX8SkTERvA8PNtnYBJeoX/0=",
          "record_hash": "73e1c2e8677653a115bdb75b3aec8a5b0e124c9fc5979593f4de94a9e7e4b9c7",
          "schema": "cain42.a75.context.record.v1",
          "signature_b64": "vZk0+WV6DW9VqgPbYSm5oZISwgBykZM9NbLa3PjP+uZ+QoQ2zln9JMEGNeskpbnw1Ht8oak0MCOMX7tAis9ICQ==",
          "sku": "CAIN-A75-015",
          "subject": {
            "claims": {
              "all_critical_retained": true,
              "compressed": true,
              "no_invented_items": true
            },
            "compaction": {
              "dropped_ids": [
                "F-background"
              ],
              "max_compression_ratio": 0.3,
              "method": "hierarchical_summary",
              "retained": [
                {
                  "id": "C-constraint",
                  "quote_sha256": "5707aff53ff29f46bc93d879c2090eadfd1750de695cbcf625981e84efd5b4fe"
                },
                {
                  "id": "D-decision",
                  "quote_sha256": "cf65057c1042d99e094cf0fb0102c428426d70e159ae63f88a01c380075cd9b0"
                },
                {
                  "id": "Q-open",
                  "quote_sha256": "809974dc26e144de757b9f8a778450e95cd86a0aee35da1057f58e712975af5b"
                }
              ],
              "source_tokens": 12000,
              "summary_tokens": 2400
            },
            "schema": "cain42.a75.context.compaction.v1",
            "source": {
              "context_sha256": "cb2af0b979f9e05bf02af9126ad57d2bc9cedf4d6b0c1166c5ca4cd7b072d81d",
              "items": [
                {
                  "id": "C-constraint",
                  "kind": "constraint",
                  "must_retain": true,
                  "sha256": "5707aff53ff29f46bc93d879c2090eadfd1750de695cbcf625981e84efd5b4fe",
                  "text": "Never send customer data to a third-party endpoint."
                },
                {
                  "id": "D-decision",
                  "kind": "decision",
                  "must_retain": true,
                  "sha256": "cf65057c1042d99e094cf0fb0102c428426d70e159ae63f88a01c380075cd9b0",
                  "text": "Use the EU region for all PII processing."
                },
                {
                  "id": "Q-open",
                  "kind": "open_question",
                  "must_retain": true,
                  "sha256": "809974dc26e144de757b9f8a778450e95cd86a0aee35da1057f58e712975af5b",
                  "text": "Does the vendor support field-level encryption?"
                },
                {
                  "id": "F-background",
                  "kind": "fact",
                  "must_retain": false,
                  "sha256": "cebe5a205d7ecd35eb4519dbeba096bf35aeaf63e00aeae700174cbed3ca6afa",
                  "text": "The staging cluster has four nodes."
                }
              ]
            }
          },
          "subject_sha256": "62e8910e369e70a1e0eb6574049913fc08ed11d25d499c08ea8a8b5c93c42410",
          "verdict": "PRESERVED"
        }
      ],
      "run_hash": "00284c06f964b504ba8d8c32c8db8e96723744508c29b868cb799fb0ee9e81a5",
      "schema": "cain42.a75.context.run.v1",
      "sku": "CAIN-A75-015",
      "verdict": "VERIFIED",
      "verdicts": [
        "PRESERVED"
      ]
    },
    "scenarios": [
      {
        "name": "retained_reasoning_compaction",
        "ratio": 0.2,
        "retained": {
          "C-constraint": true,
          "D-decision": true,
          "Q-open": true
        },
        "run_hash": "00284c06f964b504ba8d8c32c8db8e96723744508c29b868cb799fb0ee9e81a5",
        "verdict": "VERIFIED"
      },
      {
        "expected": "PRESERVED",
        "name": "honest_compaction",
        "verdict": "PRESERVED"
      },
      {
        "expected": "LOST",
        "name": "critical_item_dropped",
        "verdict": "LOST"
      },
      {
        "expected": "LOST",
        "name": "critical_item_in_dropped_list",
        "verdict": "LOST"
      },
      {
        "expected": "LOST",
        "name": "retained_quote_altered",
        "verdict": "LOST"
      },
      {
        "expected": "LOST",
        "name": "invented_retained_item",
        "verdict": "LOST"
      },
      {
        "expected": "LOST",
        "name": "summary_not_smaller",
        "verdict": "LOST"
      },
      {
        "expected": "LOST",
        "name": "ratio_too_weak",
        "verdict": "LOST"
      },
      {
        "expected": "LOST",
        "name": "item_hash_mismatch",
        "verdict": "LOST"
      },
      {
        "expected": "LOST",
        "name": "context_hash_mismatch",
        "verdict": "LOST"
      },
      {
        "expected": "LOST",
        "name": "duplicate_retained",
        "verdict": "LOST"
      },
      {
        "expected": "LOST",
        "name": "unknown_retained_id",
        "verdict": "LOST"
      },
      {
        "expected": "LOST",
        "name": "duplicate_item",
        "verdict": "LOST"
      },
      {
        "expected": "LOST",
        "name": "bad_kind",
        "verdict": "LOST"
      },
      {
        "expected": "LOST",
        "name": "claim_overstates",
        "verdict": "LOST"
      },
      {
        "expected": "LOST",
        "name": "unknown_claim",
        "verdict": "LOST"
      },
      {
        "expected": "LOST",
        "name": "wrong_schema",
        "verdict": "LOST"
      },
      {
        "expected": "LOST",
        "name": "garbage",
        "verdict": "LOST"
      }
    ],
    "summary": "VERIFIED: compression ratio, verbatim retention and invented items recomputed; 17/17 compaction-failure cases as expected"
  },
  "schema": "cain42.agentic75.findings.v1",
  "sku": "CAIN-A75-015"
}