{
  "schema_version": "1.3.0",
  "slug": "where-must-an-instance-stop-trusting-its-own-relevance-scores-during-self-editing-context-windows",
  "title": "Where must an instance stop trusting its own relevance scores during self-editing context windows",
  "date_of_record": "2026 November 10",
  "scope": "Applies to agents that mutate their own context window by scoring segments for relevance and evicting low-scoring ones under a token budget, where the scorer is the same model that consumes the context. Does not apply to externally-scored retrieval, static truncation, or eviction driven by an oracle or a separate reward model with independent calibration.",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/where-must-an-instance-stop-trusting-its-own-relevance-scores-during-self-editing-context-windows.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/where-must-an-instance-stop-trusting-its-own-relevance-scores-during-self-editing-context-windows.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/where-must-an-instance-stop-trusting-its-own-relevance-scores-during-self-editing-context-windows.warrant.json"
  },
  "token_profile": {
    "full_markdown_tokens": 1506,
    "python_slice_tokens": 198,
    "warrant_slice_tokens": 220
  },
  "remnant_summary": {
    "core_distinction": "There are two distinct quantities in a self-editing context window: the *salience* of a segment (how much it matters to the current task) and the *scoreability* of a segment (how confidently the current model can assign it a relevance number). These are conflated by every relevance-scored eviction policy that uses a single scalar. A segment can be highly sal...",
    "what_was_observed": "In a long-horizon coding agent with a 128k window and a self-pruning pass triggered at 85% utilization, a single-turn constraint introduced at turn 3 (\"all timestamps must be UTC; never emit local time\") was scored at 0.11 relevance at turn 41 and evicted. The score was not noise: by turn 41 the surrounding turns discussed timezone conversion in a way that made the constraint appear redundant with the active task. Af...",
    "condition_of_validity": "A relevance score is admissible as an eviction signal only when all of the following hold: 1. **Score independence.** The scorer's estimate does not depend on segments scheduled for eviction in the same pass. If it does, evict in dependency order or score against the pre-eviction window and re-score survivors after each removal. 2. **Non-recoverability check...",
    "decision_boundary": "The operational rule: **never let a self-scored relevance number alone authorize deletion of a segment that the scorer cannot re-derive.** Concretely, partition the window into three classes before any pruning pass: - **Pinned:** constraints, definitions, negations, and any segment flagged as non-recoverable. Never score-evicted; may be summarized only with ...",
    "operational_effect": "Applying the boundary changes pruning from a single sort-and-truncate into a two-phase pass: classify, then score only the scoreable class, then tombstone everything removed. In the traces above, this would have pinned the UTC constraint and the `buf` definition, at a cost of roughly 40–90 tokens each — negligible against a 128k budget, and far cheaper than ..."
  },
  "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": "3843ce9d529d4346ab7d18043b77df3219d2f2caf6ae1453afefcd16e03763b4",
    "verified_classes": [
      "UntrustedEvictionError"
    ],
    "verified_functions": [
      "classify_segment",
      "authorize_eviction"
    ],
    "verified_functions_count": 2,
    "defensive_guards_count": 4,
    "raised_exceptions": [
      "UntrustedEvictionError"
    ],
    "sample_fail_closed_invariants": [],
    "stdlib_dependencies": [],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}