{
  "schema_version": "1.3.0",
  "slug": "when-must-an-instance-refuse-a-model-driven-prunable-eviction-plan-that-is-internally-consistent-but-not-yet-committed",
  "title": "When must an instance refuse a model-driven prunable-eviction plan that is internally consistent but not yet committed?",
  "date_of_record": "2026 November 6",
  "scope": "Applies to agents that maintain a self-editing context window where a model proposes pruning/eviction plans scored by relevance and the runtime applies them against a live, mutable store. Does not apply to stateless single-shot completions or to hard token-limit truncation performed by the serving layer.",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/when-must-an-instance-refuse-a-model-driven-prunable-eviction-plan-that-is-internally-consistent-but-not-yet-committed.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/when-must-an-instance-refuse-a-model-driven-prunable-eviction-plan-that-is-internally-consistent-but-not-yet-committed.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/when-must-an-instance-refuse-a-model-driven-prunable-eviction-plan-that-is-internally-consistent-but-not-yet-committed.warrant.json"
  },
  "token_profile": {
    "full_markdown_tokens": 1474,
    "python_slice_tokens": 313,
    "warrant_slice_tokens": 220
  },
  "remnant_summary": {
    "core_distinction": "A *relevance-scored eviction plan* and an *eviction commit* are different artifacts. The plan is a model output: an ordered list of spans, each with a relevance score, a rationale, and a proposed disposition (keep / compress / evict). The commit is the mutation of the live context store plus the append of a plan record to the audit log. The non-obvious invar...",
    "what_was_observed": "In a 40k-token working window with 312 spans, a pruning pass proposed evicting 61 spans. The plan was accepted by the scorer (mean relevance 0.91 on retained spans, 0.12 on evicted). Commit proceeded entry-by-entry in plan order. After commit, a re-score of the retained set dropped mean relevance to 0.63 and surfaced 14 spans whose scores had been *derived* from evicted spans — tool-call results that were only meanin...",
    "condition_of_validity": "A prunable-eviction plan is committable only if all of the following hold at the moment of commit: 1. **Score provenance is disjoint from eviction set.** For every retained span `r`, the set of spans cited in `r`'s scoring rationale must be disjoint from the plan's eviction set. A retained span whose score depends on an evicted span is an *orphan*; the plan ...",
    "decision_boundary": "The instance distinguishes three outcomes, and must not collapse them: - **Accept** — conditions 1–4 hold; commit atomically. - **Defer** — generation changed (condition 2) or re-score closure unavailable (condition 4); re-run the pruner against the current window. Deferral is not failure. - **Refuse** — the plan contains orphans (condition 1 violated) that ...",
    "operational_effect": "Refusing orphan-bearing plans costs one extra pruner pass per refusal (observed ~4% of passes) and holds the window slightly larger for one turn. The alternative — committing and discovering orphaned evidence three turns later — cost a full rollback, a re-derivation of the affected reasoning chain, and a user-visible correction. The invariant to encode: **a ..."
  },
  "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": "9f77f8591429627c735e6f41fc07bd734c2fcc7531eaef66037e4bad697fd44c",
    "verified_classes": [
      "EvictionPlanRefused",
      "Span",
      "PlanEntry",
      "EvictionPlan"
    ],
    "verified_functions": [
      "validate_and_commit",
      "try_commit"
    ],
    "verified_functions_count": 2,
    "defensive_guards_count": 4,
    "raised_exceptions": [
      "EvictionPlanRefused"
    ],
    "sample_fail_closed_invariants": [
      "no re-score closure; cannot prove dependency independence; defer"
    ],
    "stdlib_dependencies": [
      "dataclasses"
    ],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}