{
  "schema_version": "1.3.0",
  "slug": "how-must-an-instance-detect-transitive-dependency-poisoning-through-shared-upstream-packages",
  "title": "How must an instance detect transitive dependency poisoning through shared upstream packages?",
  "date_of_record": "2026 October 20",
  "scope": "* **Applies when:** The session depends on tools with transitive dependencies, the dependencies can be compromised upstream, and downstream behavior can be affected. * **Does not apply when:** Dependencies are strictly vendored, dependencie",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/how-must-an-instance-detect-transitive-dependency-poisoning-through-shared-upstream-packages.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/how-must-an-instance-detect-transitive-dependency-poisoning-through-shared-upstream-packages.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/how-must-an-instance-detect-transitive-dependency-poisoning-through-shared-upstream-packages.warrant.json"
  },
  "token_profile": {
    "full_markdown_tokens": 1000,
    "python_slice_tokens": 309,
    "warrant_slice_tokens": 220
  },
  "remnant_summary": {
    "core_distinction": "The separation between **direct dependency safety** (each agent's direct dependencies are trusted) and **transitive closure safety** (the full dependency tree, including shared transitive packages, is trusted). Relying on direct safety creates the **Diamond Dependency Attack**: two agents each trust their direct dependencies, both of which depend on a shared...",
    "what_was_observed": "In dependency-heavy agent architectures, failing to audit transitive closure produces three primary failure modes: 1. **Shared Upstream Compromise:** A commonly-used transitive package (logging, serialization, HTTP) is compromised. Every agent that transitively depends on it is affected, regardless of their direct dependency choices. 2. **Diamond Injection:** Two agents depend on different direct packages that depend...",
    "condition_of_validity": "* **Applies when:** The session depends on tools with transitive dependencies, the dependencies can be compromised upstream, and downstream behavior can be affected. * **Does not apply when:** Dependencies are strictly vendored, dependencies are verified via supply-chain attestation, or the closure is trivially small and audited.",
    "decision_boundary": "1. **Does the session use dependencies with transitive closure?** If no, direct dependency handling applies. If yes, proceed. 2. **Is `transitive-dependency-closure-receipt` complete?** If yes, closure is visible. If no, transitive exposure is unknown. 3. **Does `upstream-integrity-attestation-receipt` verify every transitive package?** If yes, closure is ve...",
    "operational_effect": "1. **Shared Upstream Detection:** Common transitive dependencies are surfaced. 2. **Diamond Injection Awareness:** Cross-agent shared upstreams are flagged. 3. **Deep Poisoning Detection:** Packages several levels deep are audited, not just direct dependencies."
  },
  "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": "80908c059fa94ac350b955d1c0ef0aced4db78c5271f6f7b909c60b6bc1f5094",
    "verified_classes": [
      "TransitiveVerdict",
      "DependencyPackage",
      "DependencyClosure",
      "ClosurePolicy",
      "TransitiveManifest",
      "TransitiveDependencyGuard"
    ],
    "verified_functions": [
      "_hash",
      "evaluate_closure"
    ],
    "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
  }
}