rung: 1
name: "[[4,2,2]] Encoded Magic-State Preparation"
description: "Baseline ratchet over preparation, verification, and postselection choices for the smallest encoded magic-state experiment."
objective: "Maximize acceptance-weighted encoded magic quality for [[4,2,2]] T-state preparation on a backend-aware cheap tier."

bootstrap_incumbent:
  seed_style: h_p
  encoder_style: cx_chain
  verification: both
  postselection: all_measured
  ancilla_strategy: dedicated_pair
  optimization_level: 2
  layout_method: sabre
  routing_method: sabre
  approximation_degree: 1.0
  target_backend: fake_brisbane
  noise_backend: fake_brisbane
  shots: 512
  repeats: 2
  notes: "Bootstrap incumbent for encoded T-state preparation."

search_space:
  max_challengers_per_step: 8
  dimensions:
    seed_style: [h_p, ry_rz, u_magic]
    encoder_style: [cx_chain, cz_compiled]
    verification: [both, z_only, x_only]
    postselection: [all_measured, z_only, none]
    ancilla_strategy: [dedicated_pair, reused_single]
    optimization_level: [1, 2, 3]

tier_policy:
  cheap_margin: 0.002
  confirmation_margin: 0.0
  cheap_shots: 512
  expensive_shots: 1024
  cheap_repeats: 2
  expensive_repeats: 1
  promote_top_k: 2
  enable_hardware: false
  confirm_incumbent_on_hardware: true
  hardware_budget: 1

score:
  name: weighted_acceptance_cost
  base_cost: 1.0
  cheap_quality:
    ideal_fidelity: 0.10
    noisy_fidelity: 0.40
    logical_witness: 0.25
    codespace_rate: 0.15
    stability_score: 0.05
    spectator_alignment: 0.05
  expensive_quality:
    logical_witness: 0.55
    codespace_rate: 0.15
    stability_score: 0.20
    spectator_alignment: 0.10
  cost_weights:
    two_qubit_count: 0.08
    depth: 0.01
    shot_count: 0.00020
    runtime_estimate: 0.015
    queue_cost_proxy: 0.30

step_budget: 3
patience: 2

hardware:
  backend_name:
  channel:
  instance:
  token_env_var: QISKIT_IBM_TOKEN