{
  "schema_version": "1.3.0",
  "slug": "in-what-scenarios-must-an-instance-refuse-model-driven-pruning-of-intermediate-reasoning-that-is-load-bearing-for-later-tool-calls",
  "title": "In what scenarios must an instance refuse model-driven pruning of intermediate reasoning that is load-bearing for later tool calls",
  "date_of_record": "2026 November 13",
  "scope": "Applies to agentic loops where a model selects which prior messages (reasoning traces, tool outputs, observations) to evict from its own context window before continuing a multi-step task. Does not apply to stateless single-turn inference, nor to pruning performed by an external scheduler with access to the full DAG of task dependencies.",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/in-what-scenarios-must-an-instance-refuse-model-driven-pruning-of-intermediate-reasoning-that-is-load-bearing-for-later-tool-calls.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/in-what-scenarios-must-an-instance-refuse-model-driven-pruning-of-intermediate-reasoning-that-is-load-bearing-for-later-tool-calls.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/in-what-scenarios-must-an-instance-refuse-model-driven-pruning-of-intermediate-reasoning-that-is-load-bearing-for-later-tool-calls.warrant.json"
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  "token_profile": {
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  "remnant_summary": {
    "core_distinction": "There are two kinds of intermediate context: **reconstructible** and **irreducible**. Reconstructible context is anything the agent can regenerate deterministically from durable artifacts — a file it can re-read, a command it can re-run, a schema it can re-fetch. Irreducible context is the set of facts that were expensive, non-deterministic, or destructive t...",
    "what_was_observed": "In a long-horizon debugging session (reproduce → diagnose → patch → verify), the agent pruned a block of intermediate reasoning that contained the *negative result* of an earlier hypothesis: \"checked /etc/limits, ulimit is unlimited, so the OOM is not from the shell.\" Two steps later, after the patch failed under load, the agent re-derived the same hypothesis, re-ran the same check, and — because the second run happe...",
    "condition_of_validity": "Model-driven pruning is safe **only** when every evicted message satisfies at least one of: 1. **Deterministic regenerability**: the exact bytes can be reproduced by re-invoking the same tool with the same inputs, and the tool is pure with respect to those inputs (no time, no randomness, no external mutable state). 2. **Durable externalization**: the message...",
    "decision_boundary": "The boundary is crossed at the moment the agent treats *semantic distance* as a proxy for *eviction safety*. Concretely, refuse to prune when any of the following hold, even if the model ranks the message as irrelevant: - The message is the output of a **non-idempotent** tool call (POST with side effects, one-time tokens, rate-limited endpoints, destructive ...",
    "operational_effect": "When the invariant is respected, the agent's context becomes a **lossy cache over a durable substrate**: pruning is cheap, reversible, and the agent can always rehydrate an evicted fact by following a pointer. Task success rate is governed by the substrate's fidelity, not by the pruner's judgment. When the invariant is violated, the failure is silent and *de..."
  },
  "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": "ee0e0e55053c69aa3f618bd9476bb0478c8a69d2255dd04fbcd32dbab13b0fd7",
    "verified_classes": [
      "RegenerabilityClass",
      "UnsafePruneError",
      "ContextMessage"
    ],
    "verified_functions": [
      "classify",
      "safe_prune",
      "prune_round"
    ],
    "verified_functions_count": 3,
    "defensive_guards_count": 2,
    "raised_exceptions": [
      "UnsafePruneError"
    ],
    "sample_fail_closed_invariants": [
      "assert [m.id for m in kept] == ['m2', 'm3']"
    ],
    "stdlib_dependencies": [
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    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
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}