{
  "schema_version": "sn91-candidate-change-manifest/v1",
  "candidate": "profilefix-no-short-no-counter-v1",
  "baseline": "profilefix-no-short-v1",
  "changes": [
    {
      "id": "retain-disabled-genuine-short-emissions",
      "scope": "length assignment only",
      "before": {
        "short_context_fraction": 0.0
      },
      "after": {
        "short_context_fraction": 0.0
      },
      "justification": "Preserve profilefix-no-short-v1's full-context training geometry."
    },
    {
      "id": "replace-counter-assigned-rows",
      "scope": "rows selected as prefix_cumulative_counter only",
      "selector_probability": 0.025,
      "replacement": {
        "families": "first fourteen UID131-derived base families",
        "weights": "normalized Profilefix weights for those families, exactly UID131 relative composition",
        "context_length": 4096,
        "ordinary_measurement_artifacts": true,
        "uid131_global_seasonal_bank": true,
        "rng": {
          "kind": "numpy SeedSequence child stream",
          "spawn_key_hex": ["4e4f434e", "545231"],
          "consumes_main_rng": false
        }
      },
      "justification": "Isolate the counter family's large tail regressions without reshuffling any non-counter row."
    }
  ],
  "preserved": {
    "profilefix_counter_selector_mass": true,
    "original_counter_builder_main_rng_consumption": true,
    "all_non_counter_rows_byte_identical": true,
    "short_selector_rng_draws": true,
    "short_length_bucket_rng_draws": true,
    "genuine_short_outputs_disabled": true,
    "profilefix_padding_selector": true,
    "profilefix_global_seasonal_bank_for_non_counter_rows": true,
    "thread_local_seasonal_bank_isolation": true,
    "thread_local_default_is_explicit_false": true,
    "requirements_byte_identical": true
  },
  "causal_identity_check": {
    "seed": 129,
    "chunk_size": 64,
    "rows": 193,
    "counter_oracle": "sentinel wrapper that first consumes the original builder",
    "baseline": "profilefix-no-short-v1",
    "all_non_counter_rows_byte_identical": true,
    "all_counter_rows_replaced": true,
    "all_outputs_length_4096": true,
    "two_thread_seasonal_context_non_leak": true
  },
  "known_risks": [
    "Generating and discarding original counter rows adds CPU overhead.",
    "A 2.5% replacement may be too small to move paired score."
  ],
  "required_promotion_gate": {
    "paired_uid131_gpu_ab": true,
    "fresh_source_disjoint_public_pool": true,
    "treasury_and_finance_regression_veto": true,
    "throughput_at_least_uid131_0_98": true,
    "all_outputs_length_4096": true,
    "currently_satisfied": false
  }
}