{
  "schema_version": "1.3.0",
  "slug": "which-invariants-prevent-false-forget-verification-in-read-write-forget-memory-tool-schemas",
  "title": "Which invariants prevent false forget-verification in read/write/forget memory tool schemas",
  "date_of_record": "2026 November 9",
  "scope": "Applies to any agent runtime exposing `read`, `write`, and `forget` (or `delete`/`purge`) memory tools where `forget` returns a success signal and a subsequent `read` is used to confirm erasure. Does not apply to append-only stores where physical deletion is deferred to a compaction job with its own audit trail, nor to systems where `forget` is synchronous and returns a tombstone with a monotonic sequence number.",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/which-invariants-prevent-false-forget-verification-in-read-write-forget-memory-tool-schemas.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/which-invariants-prevent-false-forget-verification-in-read-write-forget-memory-tool-schemas.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/which-invariants-prevent-false-forget-verification-in-read-write-forget-memory-tool-schemas.warrant.json"
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  "token_profile": {
    "full_markdown_tokens": 1341,
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    "warrant_slice_tokens": 220
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  "remnant_summary": {
    "core_distinction": "The distinction that matters is between **logical erasure** (the key is no longer addressable by the current session, index, or namespace) and **verifiable erasure** (a read issued *after* the forget, against the *same* addressing path, returns a definitive absence rather than a stale or default value). Most `forget` implementations return success on logical...",
    "what_was_observed": "An agent issued `forget(key=\"user_pref_timezone\")`, received `{\"status\": \"ok\"}`, then issued `read(key=\"user_pref_timezone\")` and received `{\"value\": \"\"}`. The agent logged the forget as verified. Three turns later, a `read` on a differently-cased key (`User_Pref_Timezone`) returned the original value `\"America/Denver\"`. The forget had been applied to a case-sensitive index; the read-verification had hit a case-insen...",
    "condition_of_validity": "The read-after-forget verification is valid **only if** all of the following hold: 1. The `read` is routed to the same consistency domain (primary, same namespace, same case-folding rules) as the `forget`. 2. The schema defines a distinct absence sentinel (`KeyNotFound` / `404` / explicit `found: false`) separate from any empty value the key could legitimate...",
    "decision_boundary": "When the schema cannot satisfy all four conditions, the correct decision is to **treat the forget as unverified and escalate**, not to treat the empty read as confirmation. Concretely: - If `read` returns a zero value with no absence sentinel → **unverified**, do not log as erased. - If `read` returns `KeyNotFound` but the path differs from the forget path (...",
    "operational_effect": "Agents that treat empty reads as forget-confirmation silently accumulate \"verified\" erasures that are not erased. This is worse than an unverified forget, because the audit log now contains a false attestation that downstream compliance or privacy logic will trust. The operational rule: **never verify a forget with a read whose schema does not distinguish ab..."
  },
  "matched_failure_symptoms": [
    "OOM_KILL_OR_MEMORY_EXHAUSTION",
    "SCHEMA_DRIFT_OR_COERCION_CRASH"
  ],
  "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": "26253fbb3580b4b77204e22ce0a181fddc48bd105b9a5e6043725c248f7bc905",
    "verified_classes": [
      "ForgetVerificationError"
    ],
    "verified_functions": [
      "verify_forget",
      "forget_and_verify"
    ],
    "verified_functions_count": 2,
    "defensive_guards_count": 3,
    "raised_exceptions": [
      "ForgetVerificationError"
    ],
    "sample_fail_closed_invariants": [],
    "stdlib_dependencies": [],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}