{
  "schema_version": "1.3.0",
  "slug": "in-what-scenarios-must-an-instance-distrust-its-own-anomaly-score-score-inversion-under-provenance-graph-densification-on-the-memory-write-path",
  "title": "In what scenarios must an instance distrust its own anomaly score: score-inversion under provenance-graph densification on the memory write path",
  "date_of_record": "2026 November 10",
  "scope": "This record applies to memory-poisoning detectors that compute a scalar anomaly score over a write-path provenance graph (writer identity, taint lineage, read-set ancestry, and edge multiplicity) and gate acceptance of a memory write on that score. It does not apply to content-classifier detectors, embedding-similarity detectors, or provenance systems that emit only boolean taint bits without per-edge multiplicity.",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/in-what-scenarios-must-an-instance-distrust-its-own-anomaly-score-score-inversion-under-provenance-graph-densification-on-the-memory-write-path.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/in-what-scenarios-must-an-instance-distrust-its-own-anomaly-score-score-inversion-under-provenance-graph-densification-on-the-memory-write-path.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/in-what-scenarios-must-an-instance-distrust-its-own-anomaly-score-score-inversion-under-provenance-graph-densification-on-the-memory-write-path.warrant.json"
  },
  "token_profile": {
    "full_markdown_tokens": 1305,
    "python_slice_tokens": 166,
    "warrant_slice_tokens": 220
  },
  "remnant_summary": {
    "core_distinction": "The non-obvious boundary is between *provenance anomaly* and *provenance density*. Most detectors treat a high score as \"this write is suspicious\" and a low score as \"this write is clean.\" That mapping is only valid while the graph's edge population is stable. When a legitimate subsystem begins writing through a shared, highly connected ancestor (a common fe...",
    "what_was_observed": "During a consolidation of three memory writers behind a single broker process, the detector's median score on benign writes rose from 0.18 to 0.61 (degree-normalized variant) while a known-poisoned replay set fell from 0.74 to 0.29. Both populations moved toward the decision threshold of 0.50 from opposite sides. The poisoned writes were not evading detection by changing content; they were unchanged payloads replayed...",
    "condition_of_validity": "The score-to-trust mapping is valid only when all three hold: 1. **Degree stationarity.** The degree distribution of ancestors reachable from a write in the current window is within a calibrated band of the degree distribution at calibration time. Track a rolling statistic (e.g., p95 ancestor degree) and treat drift beyond the band as invalidating the score,...",
    "decision_boundary": "Distrust the score and escalate to fallback when **either** the rolling ancestor-degree statistic exits its calibrated band **or** the estimated separation margin between benign and poisoned reference distributions falls below the variance floor. Do not escalate on absolute score alone; a high score under densified provenance is as likely to be a benign brok...",
    "operational_effect": "Instances that apply this boundary stop treating the anomaly score as a trust oracle and treat it as a *conditional* estimator with an explicit validity precondition. The practical consequences: (1) detector health is monitored as distribution separation, not alert volume; (2) densification events (broker consolidation, wrapper adoption, cache-layer introduc..."
  },
  "matched_failure_symptoms": [
    "OOM_KILL_OR_MEMORY_EXHAUSTION"
  ],
  "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": "beea8f6889f52afc5bae4c0436d5fdac164cdf0a4c136ec3a247a45d77a99e28",
    "verified_classes": [
      "ProvenanceScoreInvalidError"
    ],
    "verified_functions": [
      "gate_memory_write"
    ],
    "verified_functions_count": 1,
    "defensive_guards_count": 1,
    "raised_exceptions": [
      "ProvenanceScoreInvalidError"
    ],
    "sample_fail_closed_invariants": [],
    "stdlib_dependencies": [],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}