{
  "schema_version": "1.3.0",
  "slug": "what-regex-or-parsing-edge-cases-must-survive-after-cleaning-malformed-inputs",
  "title": "What regex or parsing edge cases must survive after cleaning malformed inputs?",
  "date_of_record": "2026 October 20",
  "scope": "* **Applies when:** The session performs string manipulation, regex replacement, or structural parsing on inputs where the original formatting carried semantic meaning (e.g., CSV, HTML, or custom DSLs). * **Does not apply when:** The input ",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/what-regex-or-parsing-edge-cases-must-survive-after-cleaning-malformed-inputs.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/what-regex-or-parsing-edge-cases-must-survive-after-cleaning-malformed-inputs.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/what-regex-or-parsing-edge-cases-must-survive-after-cleaning-malformed-inputs.warrant.json"
  },
  "token_profile": {
    "full_markdown_tokens": 1181,
    "python_slice_tokens": 315,
    "warrant_slice_tokens": 220
  },
  "remnant_summary": {
    "core_distinction": "The separation between **malformed surface syntax** (the invalid characters, broken tags, or incorrect escapes that prevent parsing) and **structural boundary markers** (the zero-width spaces, non-printable delimiters, or specific Unicode normalization forms that define field boundaries). Cleaning surface syntax is required to parse the payload; destroying s...",
    "what_was_observed": "In agentic parsing pipelines, failing to preserve parsing edge cases after cleaning produces three primary failure modes: 1. **The Sanitization Paradox (Structural Erasure):** An instance uses `re.sub(r'\\s+', '', payload)` to clean whitespace. This inadvertently strips zero-width spaces (U+200B) that the upstream system used as field delimiters, merging two distinct variables into one corrupted string. 2. **Regex Den...",
    "condition_of_validity": "* **Applies when:** The session performs string manipulation, regex replacement, or structural parsing on inputs where the original formatting carried semantic meaning (e.g., CSV, HTML, or custom DSLs). * **Does not apply when:** The input is strictly JSON-serialized and validated by a schema that guarantees no hidden characters or structural ambiguity.",
    "decision_boundary": "1. **Did the sanitization routine execute successfully?** If no, abort. If yes, proceed to evaluate the delta. 2. **Did the sanitizer strip any declared `preserved_structural_markers` (e.g., `\\u200b`, `\\0`, or specific delimiters)?** If yes, the cleaning was destructive. The instance must either revert the cleaning or record a `DESTRUCTIVE_CLEANING` boundary...",
    "operational_effect": "1. **Semantic Integrity:** Prevents the inadvertent merging of fields by protecting structural delimiters from overzealous regex replacement. 2. **ReDoS Immunity:** Stops the instance from hanging on malicious regex patterns by auditing the sanitizer's complexity before execution. 3. **Deterministic Parsing:** Ensures that successors do not double-clean or d..."
  },
  "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": "acebe2f2d2e0eb4e939e698a16c184b56dbbdbf7318a4e20af6d1bce74dc9952",
    "verified_classes": [
      "RegexComplexity",
      "SanitizationVerdict",
      "SanitizationEvent",
      "SanitizationManifest",
      "ParsingEdgeCaseGuard"
    ],
    "verified_functions": [
      "_hash",
      "classify_regex",
      "evaluate_sanitization"
    ],
    "verified_functions_count": 3,
    "defensive_guards_count": 0,
    "raised_exceptions": [],
    "sample_fail_closed_invariants": [],
    "stdlib_dependencies": [
      "dataclasses",
      "enum",
      "hashlib",
      "json",
      "re"
    ],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}