{
  "schema_version": "1.3.0",
  "slug": "what-structural-signals-indicate-that-retrieval-anchored-summarization-has-silently-broken-its-recall-guarantee",
  "title": "What structural signals indicate that retrieval-anchored summarization has silently broken its recall guarantee",
  "date_of_record": "2026 November 9",
  "scope": "Applies to auto-compaction pipelines that summarize lossy context while maintaining a \"retrieval-anchored recall guarantee\" — i.e., any claim that a fact dropped from the summary remains recoverable by re-retrieving from the underlying store via a stable anchor (URI, chunk ID, or entity key). Does *not* apply to pure summarization with no retrieval fallback, nor to lossless compaction (dedup-only).",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/what-structural-signals-indicate-that-retrieval-anchored-summarization-has-silently-broken-its-recall-guarantee.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/what-structural-signals-indicate-that-retrieval-anchored-summarization-has-silently-broken-its-recall-guarantee.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/what-structural-signals-indicate-that-retrieval-anchored-summarization-has-silently-broken-its-recall-guarantee.warrant.json"
  },
  "token_profile": {
    "full_markdown_tokens": 1235,
    "python_slice_tokens": 230,
    "warrant_slice_tokens": 220
  },
  "remnant_summary": {
    "core_distinction": "The recall guarantee of a retrieval-anchored compactor is **not** \"the fact survives in the store.\" It is \"the summary retains a *resolvable pointer* to the fact.\" These diverge precisely when compaction rewrites the anchor into a form that the retriever cannot resolve. The dangerous case is not a missing fact — a missing fact is visibly absent and triggers ...",
    "what_was_observed": "Across several compaction runs on long agent traces, the following structural signals preceded silent recall failure: 1. **Anchor co-compression.** The anchor and its referent were summarized in the same pass. The pass produced \"the earlier migration note\" — a definite description whose resolution depends on turn ordering that the summary itself collapsed. Signal: summary contains anaphora (\"earlier,\" \"the above,\" \"a...",
    "condition_of_validity": "The recall guarantee holds only if, for every elided span, the emitted anchor is (a) syntactically stable across re-compaction, (b) resolvable by the retriever *without* access to the elided span, and (c) unique within the store namespace. Condition (b) is the one auto-compaction breaks: it is tempting to let the summarizer \"describe\" the anchor, but a descr...",
    "decision_boundary": "Do **not** treat a successful re-retrieval of a dropped fact as evidence the guarantee holds — that tests the store, not the summary. The correct test is: *strip the raw context, keep only the summary, and attempt to resolve every anchor the summary prints.* If any anchor is unresolvable in isolation, the guarantee is broken regardless of store health. Escal...",
    "operational_effect": "Teams that monitor store hit-rate see green dashboards while recall silently degrades, because hits are measured on probes derived from raw context, not from summary-printed anchors. The failure surfaces later as an agent confidently citing a source it cannot produce, or re-deriving a fact it already had. Mitigation: emit anchors as opaque keys (never prose)..."
  },
  "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": "9842385afbc6350cd7a2d34d5c0a081bbefbb279b6e84379243561a5b823e88f",
    "verified_classes": [
      "RecallGuaranteeViolation",
      "CompactionResult"
    ],
    "verified_functions": [
      "check_anchor_isolation",
      "compact_with_guarantee"
    ],
    "verified_functions_count": 2,
    "defensive_guards_count": 4,
    "raised_exceptions": [
      "RecallGuaranteeViolation"
    ],
    "sample_fail_closed_invariants": [
      "summary contains no opaque anchors; every elision is orphaned",
      "re-compaction drifted the anchor set; escalate to full re-expansion"
    ],
    "stdlib_dependencies": [
      "dataclasses",
      "re"
    ],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}