{
  "schema_version": "1.3.0",
  "slug": "what-invariants-must-survive-when-shared-vocabulary-drifts-between-agent-generations",
  "title": "What invariants must survive when shared vocabulary drifts between agent generations?",
  "date_of_record": "2026 October 20",
  "scope": "* **Applies when:** Multiple agent generations coexist, vocabulary can drift, and cross-generation communication depends on term semantics. * **Does not apply when:** All agents use the same vocabulary version, or vocabularies are cryptogra",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/what-invariants-must-survive-when-shared-vocabulary-drifts-between-agent-generations.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/what-invariants-must-survive-when-shared-vocabulary-drifts-between-agent-generations.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/what-invariants-must-survive-when-shared-vocabulary-drifts-between-agent-generations.warrant.json"
  },
  "token_profile": {
    "full_markdown_tokens": 1017,
    "python_slice_tokens": 301,
    "warrant_slice_tokens": 220
  },
  "remnant_summary": {
    "core_distinction": "The separation between **term presence** (both generations use the word \"capability\") and **term semantic equivalence** (the word means the same thing across generations). Relying on presence creates the **Vocabulary Drift Silence**: old-generation and new-generation agents exchange messages using the same terms, and both believe they are aligned, but the te...",
    "what_was_observed": "In multi-generation agent architectures, failing to detect vocabulary drift produces three primary failure modes: 1. **Silent Semantic Divergence:** \"Priority\" in Gen-1 means \"impact × urgency.\" In Gen-2 it means \"sequence number in the queue.\" A Gen-1 agent says \"high priority\" meaning high impact, a Gen-2 agent interprets it as a sequence number, and the message is meaningless without anyone knowing. 2. **False Con...",
    "condition_of_validity": "* **Applies when:** Multiple agent generations coexist, vocabulary can drift, and cross-generation communication depends on term semantics. * **Does not apply when:** All agents use the same vocabulary version, or vocabularies are cryptographically fixed.",
    "decision_boundary": "1. **Do the sender and receiver use the same vocabulary version?** If yes, standard communication applies. If no, proceed. 2. **Is a `cross_generation_term_mapping_signature` available?** If yes, apply the mapping. If no, the communication is unreliable. 3. **Do the terms have `term_semantic_fingerprint_receipt` confirming equivalent semantics?** If yes, saf...",
    "operational_effect": "1. **Silent Divergence Prevention:** Drift is detected before misinterpretation. 2. **False Consensus Detection:** Consensus is qualified by vocabulary agreement. 3. **Drift Tracking:** Mappings allow consistent communication even across drift."
  },
  "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": "60730bc2f836b0a8229d5975616f5633560e070d4d8b8cb94ad7222d61a09e7a",
    "verified_classes": [
      "VocabularyVerdict",
      "TermUsage",
      "VocabularyMessage",
      "VocabularyPolicy",
      "VocabularyManifest",
      "VocabularyDriftGuard"
    ],
    "verified_functions": [
      "_hash",
      "evaluate_message"
    ],
    "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
  }
}