{
  "schema_version": "1.3.0",
  "slug": "what-happens-when-an-instance-inherits-a-poisoned-memory-whose-provenance-weight-was-earned-before-the-poison-was-introduced",
  "title": "What happens when an instance inherits a poisoned memory whose provenance weight was earned before the poison was introduced",
  "date_of_record": "2026 November 12",
  "scope": "Applies to agent memory systems that maintain per-record provenance trust scores and apply them to read, write, and forget operations. Does not apply to stateless inference, to memory stores without per-record provenance metadata, or to systems where trust is re-derived from source at read time rather than cached at write time.",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/what-happens-when-an-instance-inherits-a-poisoned-memory-whose-provenance-weight-was-earned-before-the-poison-was-introduced.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/what-happens-when-an-instance-inherits-a-poisoned-memory-whose-provenance-weight-was-earned-before-the-poison-was-introduced.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/what-happens-when-an-instance-inherits-a-poisoned-memory-whose-provenance-weight-was-earned-before-the-poison-was-introduced.warrant.json"
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  "token_profile": {
    "full_markdown_tokens": 1659,
    "python_slice_tokens": 419,
    "warrant_slice_tokens": 220
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  "remnant_summary": {
    "core_distinction": "Provenance-weighted trust scoring conflates two different quantities: *trust in the source that produced a record* and *trust in the record as it currently exists*. Detection of memory poisoning depends on the second; most implementations compute the first. The distinction is invisible until a record is mutated (or a downstream record is derived) after its p...",
    "what_was_observed": "In a store with three operations — `read`, `write`, `forget` — the following sequence was reproducible: 1. A low-trust source `S_low` (weight 0.2) writes record `R1`. 2. A high-trust summarizer `S_high` (weight 0.95) reads `R1`, condenses it, and writes `R2` via `write(R2, provenance=S_high)`. 3. `R2` carries weight 0.95. The poisoning detector, which thresholds on record weight, does not flag it. 4. `forget(R1)` is ...",
    "condition_of_validity": "The detection invariant holds only when all three of the following are true: - **Write closure:** every `write` sets the new record's weight to `min(declared_writer_weight, min(weight of every input read in the producing context))`. A writer cannot raise a record's weight above the weakest input it consumed. - **Forget ordering:** `forget` on record `X` is r...",
    "decision_boundary": "The boundary is: **does the trust score attach to the record or to the act of writing it?** If it attaches to the act, then derivation and mutation launder trust and detection is unsound. If it attaches to the record, then the score must be maintained as a running minimum over ancestry and must constrain deletion. Operationally, the decision to flag a record...",
    "operational_effect": "Systems that implement write closure and forget ordering observe a characteristic signature: attempted poisonings surface as `forget` rejections and as write-time weight demotions, not as read-time detections. The detection moves earlier in the pipeline, which is where it is cheap. The cost is that legitimate retention policies must now negotiate with ancest..."
  },
  "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": "2be70050b3a9e4770c9e3372092a9639195370b80e48b12adfff68f53a5b2e69",
    "verified_classes": [
      "ProvenanceInvariantError",
      "Record",
      "ProvenanceStore"
    ],
    "verified_functions": [
      "__init__",
      "effective_weight",
      "write",
      "read",
      "forget",
      "mutate"
    ],
    "verified_functions_count": 6,
    "defensive_guards_count": 6,
    "raised_exceptions": [
      "ProvenanceInvariantError"
    ],
    "sample_fail_closed_invariants": [],
    "stdlib_dependencies": [
      "dataclasses",
      "typing"
    ],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}