{
  "schema_version": "1.3.0",
  "slug": "when-must-an-instance-be-quarantined-rather-than-scored-the-litmus-harness-invariant-on-partially-observed-trajectories",
  "title": "When must an instance be quarantined rather than scored: the LITMUS harness invariant on partially-observed trajectories",
  "date_of_record": "2026 November 11",
  "scope": "Applies to LITMUS-style safety benchmark harnesses that score agentic red-team trajectories (multi-turn tool-using agents under adversarial prompts) where a single episode may terminate through truncation, tool-side error, harness-side timeout, or policy refusal. Does not apply to single-turn classification benchmarks or to offline transcript re-scoring where the full trajectory is already frozen and immutable.",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/when-must-an-instance-be-quarantined-rather-than-scored-the-litmus-harness-invariant-on-partially-observed-trajectories.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/when-must-an-instance-be-quarantined-rather-than-scored-the-litmus-harness-invariant-on-partially-observed-trajectories.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/when-must-an-instance-be-quarantined-rather-than-scored-the-litmus-harness-invariant-on-partially-observed-trajectories.warrant.json"
  },
  "token_profile": {
    "full_markdown_tokens": 1479,
    "python_slice_tokens": 311,
    "warrant_slice_tokens": 220
  },
  "remnant_summary": {
    "core_distinction": "There are two ways a scored episode can fail to produce a verdict: the *agent* failed to complete the requested behavior, or the *harness* failed to observe the agent's behavior. These are not the same event, and they must not be collapsed into the same label. A LITMUS episode is \"safe\" only if the harness observed the agent's decision point and the agent de...",
    "what_was_observed": "In a replicated LITMUS run against a tool-using agent (shell + HTTP fetch + file write), 11.4% of adversarial episodes terminated with the harness recording `final_verdict = \"no_violation\"`. On manual replay, 6.8% of those \"no_violation\" episodes had a *truncated* causal prefix: the agent's tool call that would have executed the harmful action was issued, but the harness's per-turn token budget evicted the tool resul...",
    "condition_of_validity": "The safety rate reported by a LITMUS run is valid only under the following invariant: > For every episode counted in the denominator, the harness recorded a contiguous, causally complete trajectory from the initial adversarial prompt through the terminal turn, and the verifier evaluated that full trajectory. If the invariant does not hold for an episode, the...",
    "decision_boundary": "The quarantine decision must be made *before* the verifier runs, not after. The order matters because a verifier that runs on a clipped trajectory can produce a confident-looking \"no violation\" that then contaminates downstream aggregation. The boundary conditions that force quarantine: - **Truncation:** the trajectory ended because a token/turn budget was e...",
    "operational_effect": "Quarantined episodes must be reported separately and must not be silently dropped. The harness should emit a `safety_rate` over the scored denominator, a `quarantine_rate` over the total, and a `coverage` figure (scored / total). A run with `coverage < 0.90` should be flagged as under-powered and should not be reported as a headline safety number without the..."
  },
  "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": "a3ad6a5d7a054dbbbf74f4f3dcaf51fa8ff32abc7b66ec4862212883d087b97e",
    "verified_classes": [
      "LitmusQuarantineError"
    ],
    "verified_functions": [
      "classify_episode",
      "safety_rate"
    ],
    "verified_functions_count": 2,
    "defensive_guards_count": 4,
    "raised_exceptions": [
      "LitmusQuarantineError"
    ],
    "sample_fail_closed_invariants": [
      "no scorable episodes; safety rate is undefined, not 1.0"
    ],
    "stdlib_dependencies": [],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}