{
  "contract_schema": "nmd-vcell-vcc-evaluation-contract/1.0",
  "feature_build": "VCC-EVAL-20260729-02",
  "resource_release": "v1.0.0-database-resource",
  "native_benchmark_release": "repeated-fold-v2.2",
  "state": "PREREGISTERED_TEMPLATE_TASK_UNDISCLOSED",
  "task_binding": {
    "challenge_year": 2026,
    "problem_id": null,
    "cell_context": null,
    "perturbation_modality": null,
    "prediction_unit": null,
    "expression_space": null,
    "training_accessions": [],
    "hidden_test_definition": null,
    "official_metric_weights": null,
    "binding_state": "WAITING_FOR_2026_RULES",
    "null_semantics": "Null fields are intentionally unbound because Arc has not released the task specification."
  },
  "baseline_profiles": [
    {
      "baseline_id": "zero_change",
      "state": "IMPLEMENTED_NATIVE",
      "fit_scope": "none",
      "leakage_rule": "emits zero perturbation response"
    },
    {
      "baseline_id": "outer_train_mean",
      "state": "IMPLEMENTED_NATIVE",
      "fit_scope": "outer_training_targets_only",
      "leakage_rule": "recomputed independently inside every outer fold"
    },
    {
      "baseline_id": "regularized_linear_ridge",
      "state": "IMPLEMENTED_NATIVE",
      "fit_scope": "outer_training_targets_only",
      "leakage_rule": "imputation, scaling and alpha selection are training-fold only"
    },
    {
      "baseline_id": "nearest_neighbor_perturbation",
      "state": "REGISTERED_NOT_IMPLEMENTED",
      "fit_scope": "training_targets_only",
      "leakage_rule": "neighbour search excludes all validation/test targets and outcomes"
    },
    {
      "baseline_id": "public_open_model",
      "state": "REGISTERED_NOT_BOUND",
      "fit_scope": "official_task_dependent",
      "leakage_rule": "requires identical inputs, gene space, prediction unit and hidden split"
    }
  ],
  "split_profiles": [
    {
      "split_id": "same_context_unseen_perturbation",
      "state": "IMPLEMENTED_NATIVE",
      "grouping_unit": "perturbation_target",
      "current_context": "HepG2"
    },
    {
      "split_id": "leave_one_donor_out",
      "state": "REGISTERED_DATA_MISSING",
      "grouping_unit": "donor"
    },
    {
      "split_id": "leave_one_dataset_out",
      "state": "REGISTERED_DATA_MISSING",
      "grouping_unit": "source_accession"
    },
    {
      "split_id": "leave_one_disease_stage_out",
      "state": "REGISTERED_DATA_MISSING",
      "grouping_unit": "disease_stage"
    },
    {
      "split_id": "cross_cell_context",
      "state": "EXECUTED_EXTERNAL_DIAGNOSTIC_NO_DIRECTIONAL_SUPPORT",
      "grouping_unit": "cell_type_or_context",
      "current_execution": "55-target Frangieh aggregate-delta panel; not muscle, DMD or official VCC"
    }
  ],
  "metric_profiles": [
    {
      "metric_id": "rmse",
      "family": "global_expression_error",
      "state": "IMPLEMENTED_NATIVE",
      "direction": "lower_is_better"
    },
    {
      "metric_id": "mae",
      "family": "global_expression_error",
      "state": "EXECUTED_AGGREGATE_DELTA_DIAGNOSTIC",
      "direction": "lower_is_better",
      "execution_object": "api/v1.1/vcc_metric_diagnostic.json"
    },
    {
      "metric_id": "des_deg_recovery",
      "family": "differential_expression",
      "state": "REGISTERED_REQUIRES_CELL_LEVEL_TRUTH",
      "direction": "higher_is_better"
    },
    {
      "metric_id": "pds_l1_raw",
      "family": "perturbation_discrimination",
      "state": "EXECUTED_AGGREGATE_DELTA_DIAGNOSTIC",
      "direction": "higher_is_better",
      "sensitivity_note": "prediction-vector scale must be audited",
      "execution_object": "api/v1.1/vcc_metric_diagnostic.json"
    },
    {
      "metric_id": "pds_norm_matched",
      "family": "perturbation_discrimination",
      "state": "EXECUTED_TRUTH_INFORMED_SENSITIVITY_ONLY",
      "direction": "higher_is_better",
      "sensitivity_note": "reported beside raw PDS to expose scale-dependent ranking; paired observed norms make it ineligible for hidden-test scoring",
      "execution_object": "api/v1.1/vcc_metric_diagnostic.json"
    },
    {
      "metric_id": "delta_pearson",
      "family": "effect_direction",
      "state": "EXECUTED_AGGREGATE_DELTA_DIAGNOSTIC",
      "direction": "higher_is_better",
      "execution_object": "api/v1.1/vcc_metric_diagnostic.json"
    },
    {
      "metric_id": "log_fold_change_spearman",
      "family": "effect_direction",
      "state": "REGISTERED_NOT_IMPLEMENTED",
      "direction": "higher_is_better"
    },
    {
      "metric_id": "deg_auprc",
      "family": "differential_expression",
      "state": "REGISTERED_REQUIRES_CELL_LEVEL_TRUTH",
      "direction": "higher_is_better"
    },
    {
      "metric_id": "effect_size_spearman",
      "family": "effect_magnitude",
      "state": "EXECUTED_AGGREGATE_DELTA_DIAGNOSTIC",
      "direction": "higher_is_better",
      "execution_object": "api/v1.1/vcc_metric_diagnostic.json"
    },
    {
      "metric_id": "residual_cosine",
      "family": "perturbation_specific_structure",
      "state": "IMPLEMENTED_NATIVE",
      "direction": "higher_is_better"
    },
    {
      "metric_id": "prespecified_program_recovery",
      "family": "disease_program",
      "state": "REGISTERED_MATCHED_TRUTH_MISSING",
      "direction": "higher_is_better"
    },
    {
      "metric_id": "hierarchical_uncertainty",
      "family": "uncertainty",
      "state": "IMPLEMENTED_NATIVE",
      "direction": "interval_not_rank_score"
    }
  ],
  "execution_gates": [
    "Bind the official task without changing frozen native benchmark results.",
    "Validate identical gene identifiers, expression scale and prediction unit between truth and predictions.",
    "Fit every learned baseline inside the training partition only.",
    "Report every metric separately before any aggregate rank.",
    "Publish raw and norm-matched PDS together if PDS is activated.",
    "Keep single-cell distribution metrics locked for aggregate-only predictions.",
    "Keep disease and clinical claims locked without independent functional outcomes."
  ],
  "cell_eval_adapter": {
    "state": "FORMULA_ALIGNED_AGGREGATE_ADAPTER_EXECUTED_ANNData_SUITE_NOT_EXECUTED",
    "upstream": "https://github.com/ArcInstitute/cell-eval",
    "aggregate_execution": "api/v1.1/vcc_metric_diagnostic.json",
    "activation_requirement": "predicted and observed AnnData files with official task-compatible metadata"
  },
  "claim_boundary": "The contract freezes evaluation design choices before VCC 2026 rules are known. Aggregate-delta diagnostic metrics are computed only on the frozen 55-target external panel; locked metrics remain uncomputed, the upstream AnnData suite is not executed, and no current result is task-equivalent to the future challenge."
}