{
  "schema_version": "1.3.0",
  "slug": "how-must-an-instance-handle-reference-validity-when-the-referenced-resource-changes-but-the-reference-does-not",
  "title": "How must an instance handle reference validity when the referenced resource changes but the reference does not?",
  "date_of_record": "2026 October 20",
  "scope": "* **Applies when:** References point to mutable resources, resource contracts can change, and consumers depend on specific contracts. * **Does not apply when:** Resources are immutable (content-addressed), or consumers are agnostic to contr",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/how-must-an-instance-handle-reference-validity-when-the-referenced-resource-changes-but-the-reference-does-not.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/how-must-an-instance-handle-reference-validity-when-the-referenced-resource-changes-but-the-reference-does-not.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/how-must-an-instance-handle-reference-validity-when-the-referenced-resource-changes-but-the-reference-does-not.warrant.json"
  },
  "token_profile": {
    "full_markdown_tokens": 947,
    "python_slice_tokens": 268,
    "warrant_slice_tokens": 220
  },
  "remnant_summary": {
    "core_distinction": "The separation between **reference resolvability** (the reference points to something) and **reference semantic validity** (the reference points to what the consumer expects, with the same schema, behavior, or contract). Relying on resolvability creates the **Silent Resource Drift**: the reference resolves successfully, but the resource's behavior or schema ...",
    "what_was_observed": "In long-lived reference networks, failing to detect resource drift produces three primary failure modes: 1. **Silent API Breakage:** A reference \"api.example.com/users\" resolves, but the API now returns a different schema (new required fields, removed fields, changed types), and the consumer's parser silently drops or coerces data. 2. **Behavioral Drift:** A tool's URI resolves, but the tool's behavior has changed (d...",
    "condition_of_validity": "* **Applies when:** References point to mutable resources, resource contracts can change, and consumers depend on specific contracts. * **Does not apply when:** Resources are immutable (content-addressed), or consumers are agnostic to contract changes.",
    "decision_boundary": "1. **Does the reference point to a mutable resource?** If no, standard reference handling applies. If yes, proceed. 2. **Does the `reference_contract_hash` match the `resource_contract_current_hash`?** If yes, the contract is stable. If no, the resource has drifted. 3. **Was a `contract_change_notification_receipt` received?** If yes, the consumer knew the c...",
    "operational_effect": "1. **Silent Breakage Prevention:** Contract comparison catches schema changes before they cause failures. 2. **Behavioral Transparency:** Behavioral drift is surfaced, allowing consumers to update. 3. **Version Clarity:** Versioned references let consumers pin versions, providing contract stability."
  },
  "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": "8ca8ad3ba042d6ac82f2e3a63ffdbfd0fbb113d8698d096d4b709d8132d9b293",
    "verified_classes": [
      "ContractVerdict",
      "ReferencedResource",
      "ContractPolicy",
      "ContractManifest",
      "ReferenceContractGuard"
    ],
    "verified_functions": [
      "_hash",
      "evaluate_resource"
    ],
    "verified_functions_count": 2,
    "defensive_guards_count": 0,
    "raised_exceptions": [],
    "sample_fail_closed_invariants": [],
    "stdlib_dependencies": [
      "dataclasses",
      "enum",
      "hashlib",
      "json"
    ],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}