Input

In a separate local Python environment use synthetic bounded byte strings, Unicode scalar text, JSON objects and integer lists to check roundtrips, sorting preservation and canonical normalization. Challenge four deliberately wrong variants, record shrunk witnesses, check five malformed Base64 error paths and classify an excluded surrogate. Do not invoke an AI client, upstream harness, contract engine or production service.

Acceptance criteria

Four native property families record 202 calls each including explicit cases. Four deliberately wrong fixtures are rejected with witnesses; weak idempotence alone is demonstrated, five invalid encodings rejected and an out-of-domain surrogate classified. These 15 observations are bounded native checks, not a full skill or production security evaluation.

Recorded outcome

Native Hypothesis on four synthetic property families and four intentional negative controls, five invalid encodings and an out-of-domain surrogate. No AI client, whole skill, upstream harness, smart-contract engine, paid model or production input.

{
  "executed_at": "2026-10-04T08:41:09.266631+00:00",
  "python": "3.12.4",
  "platform": "Windows-11-10.0.26300-SP0",
  "hypothesis": "6.168.3",
  "probe_sha256": "3cd2309427870c92d528112f5de1f409062d53a088d1a4ead9a8811a27513f59",
  "cases": [
    {
      "name": "base64_roundtrip",
      "status": "passed",
      "examples_executed": 202,
      "distinct_inputs": 200,
      "domain": "bounded synthetic inputs; no production data"
    },
    {
      "name": "json_utf8_roundtrip",
      "status": "passed",
      "examples_executed": 202,
      "distinct_inputs": 197,
      "domain": "bounded synthetic inputs; no production data"
    },
    {
      "name": "sort_order_and_multiplicity",
      "status": "passed",
      "examples_executed": 202,
      "distinct_inputs": 201,
      "domain": "bounded synthetic inputs; no production data"
    },
    {
      "name": "NFC_idempotence_and_canonical_preservation",
      "status": "passed",
      "examples_executed": 202,
      "distinct_inputs": 201,
      "domain": "bounded synthetic inputs; no production data"
    },
    {
      "name": "negative_control_trailing_zero_loss",
      "status": "passed",
      "counterexample_hex": "00",
      "decoded_hex": "",
      "classification": "intentional fixture implementation defect"
    },
    {
      "name": "negative_control_sort_deduplication",
      "status": "passed",
      "counterexample": [
        0,
        0
      ],
      "actual": [
        0
      ],
      "classification": "intentional fixture implementation defect"
    },
    {
      "name": "negative_control_json_field_loss",
      "status": "passed",
      "counterexample": {
        "": 0
      },
      "actual": {},
      "classification": "intentional fixture implementation defect"
    },
    {
      "name": "negative_control_constant_normalizer",
      "status": "passed",
      "counterexample": "0",
      "actual": "",
      "classification": "intentional fixture implementation defect"
    },
    {
      "name": "weak_idempotence_accepts_constant",
      "status": "passed",
      "counterexample": "0",
      "meaning": "idempotence alone misses this preservation defect"
    },
    {
      "name": "strict_base64_invalid_3f",
      "status": "passed",
      "input_ascii": "?",
      "classification": "documented error path"
    },
    {
      "name": "strict_base64_invalid_41",
      "status": "passed",
      "input_ascii": "A",
      "classification": "documented error path"
    },
    {
      "name": "strict_base64_invalid_3d3d3d",
      "status": "passed",
      "input_ascii": "===",
      "classification": "documented error path"
    },
    {
      "name": "strict_base64_invalid_413d3d3d",
      "status": "passed",
      "input_ascii": "A===",
      "classification": "documented error path"
    },
    {
      "name": "strict_base64_invalid_25252525",
      "status": "passed",
      "input_ascii": "%%%%",
      "classification": "documented error path"
    },
    {
      "name": "surrogate_outside_scalar_text_domain",
      "status": "passed",
      "classification": "out-of-domain strategy example, not an in-domain encoder bug"
    }
  ],
  "observations": 15,
  "generated_families": 4,
  "property_examples": {
    "base64_roundtrip": 202,
    "json_utf8_roundtrip": 202,
    "sort_order_and_multiplicity": 202,
    "NFC_idempotence_and_canonical_preservation": 202
  },
  "native_fixture_tested": true,
  "runtime_tested": false,
  "scope": "Native Hypothesis on four synthetic property families and four intentional negative controls, five invalid encodings and an out-of-domain surrogate. No AI client, whole skill, upstream harness, smart-contract engine, paid model or production input."
}

Environment

Isolated local Windows fixture; Python 3.12.4; Hypothesis 6.168.3; sortedcontainers 2.4.0. Synthetic data only; no production project or database, network service, AI client or upstream harness. Probe 3cd2309427870c92d528112f5de1f409062d53a088d1a4ead9a8811a27513f59

Package SHA-256: 05c12075f2dd5e468a6892d2eb15ac5e6f1f6669aaa7089b65fcbef3fdab1740

Outcome recorded: 2026-10-04 08:41 UTC