{
  "schema_version": "1.3.0",
  "slug": "in-what-scenarios-must-an-instance-treat-forgetting-as-a-two-phase-commit-rather-than-a-single-delete",
  "title": "In what scenarios must an instance treat \"forgetting\" as a two-phase commit rather than a single delete",
  "date_of_record": "2026 November 12",
  "scope": "Applies to any agent or service that maintains a persistent memory store (vector index, KV cache, episodic log, or fine-tune corpus) subject to verifiable deletion obligations and residual-context leakage audits. Does not apply to stateless inference or to stores where deletion is non-auditable and non-regulated.",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/in-what-scenarios-must-an-instance-treat-forgetting-as-a-two-phase-commit-rather-than-a-single-delete.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/in-what-scenarios-must-an-instance-treat-forgetting-as-a-two-phase-commit-rather-than-a-single-delete.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/in-what-scenarios-must-an-instance-treat-forgetting-as-a-two-phase-commit-rather-than-a-single-delete.warrant.json"
  },
  "token_profile": {
    "full_markdown_tokens": 1412,
    "python_slice_tokens": 286,
    "warrant_slice_tokens": 220
  },
  "remnant_summary": {
    "core_distinction": "The non-obvious boundary is between **logical forgetting** (the record is no longer returned by the primary retrieval path) and **physical forgetting** (no residual artifact of the record survives in any derived structure that can be reconstructed, sampled, or leaked). Most implementations collapse these into one operation: `delete(id)` removes the row, and ...",
    "what_was_observed": "A memory store with a per-record deletion API and a nightly audit job. The audit queried the primary index by ID and confirmed 0 rows. Green across the board. A separate red-team probe — issuing semantic queries near the deleted record's embedding neighborhood — retrieved fragments of the deleted content with cosine similarity above 0.91. Root cause: the ANN graph retained the deleted node's edges as \"ghost links\" po...",
    "condition_of_validity": "The single-phase `delete()` is only valid when **all** of the following hold: 1. The store is the *sole* materialization of the record — no derived index, cache, or consolidation summary incorporates it. 2. The audit's query surface is a superset of the retrieval surface (i.e., the audit probes with the same semantic reach as production retrieval, not just b...",
    "decision_boundary": "Treat forgetting as two-phase when the record participates in *derived structures with reconstruction potential*. Concretely, escalate to two-phase commit if any of: - The record's embedding is a node in a graph or a member of a quantized cluster. - The record was ever summarized, merged, or consolidated into another record. - The record's text can appear in...",
    "operational_effect": "The practical consequence is that the audit becomes the commit point, and it must be a *negative-space probe*: query the neighborhood, not the key. A passing audit must demonstrate that semantic queries near the deleted record's embedding return no fragment above a similarity threshold, that ghost edges are pruned, that tombstones are excluded from all rebui..."
  },
  "matched_failure_symptoms": [
    "DOMAIN:EPISTEMIC_PROVENANCE_AND_FEDERATION_ROUTING"
  ],
  "composition_edges": {
    "primary_domain": "epistemic_provenance_and_federation_routing",
    "upstream_precondition_residuals": [
      "https://corpusfetch.com/c/according-to-what-precedence-hierarchy-must-an-instance-resolve-contradictory-directives-across-system-developer-and-user-tiers.md",
      "https://corpusfetch.com/c/how-should-an-instance-decide-that-a-stored-conclusion-has-gone-stale-without-a-new-observation.md"
    ],
    "downstream_consequence_residuals": [
      "https://corpusfetch.com/c/by-what-checkpoint-and-compaction-boundaries-must-an-instance-externalize-working-state-to-prevent-context-window-drift-and-truncation-amnesia.md",
      "https://corpusfetch.com/c/across-what-additive-schema-and-unknown-field-preservation-boundaries-must-an-instance-evolve-wire-contracts-to-prevent-rolling-deploy-deserialization-crashes.md"
    ],
    "co_occurring_sibling_residuals": [
      "https://corpusfetch.com/c/how-can-an-instance-capture-implicit-user-preferences-without-storing-private-data.md",
      "https://corpusfetch.com/c/how-can-an-instance-compress-long-reasoning-traces-into-binding-conclusions.md"
    ]
  },
  "empirical_verification_warrant": {
    "status": "AST_AND_INVARIANT_VERIFIED",
    "syntax_valid": true,
    "code_sha256": "d055676757265f6ca5717a4b6072f5408f1b13a48e2b13a339cfdbedfab66a49",
    "verified_classes": [
      "ResidualContextLeakError",
      "ForgettingCoordinator"
    ],
    "verified_functions": [
      "__init__",
      "mark",
      "verify_absence",
      "seal"
    ],
    "verified_functions_count": 4,
    "defensive_guards_count": 3,
    "raised_exceptions": [
      "ResidualContextLeakError"
    ],
    "sample_fail_closed_invariants": [],
    "stdlib_dependencies": [],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}