{
  "task_id": "reaction-kinetics",
  "version": "0.2.0",
  "budget": 3,
  "cost_semantics": "Every accepted experiment costs one credit; at most two repeats per action. Invalid requests cost nothing. The budget is a hard constraint; unused credits do not directly increase the score.",
  "measurement_noise": "Independent additive zero-mean Gaussian noise per output and replicate, with the listed fixed standard deviations. Readouts are not clipped. Each measurement has equal synthetic exposure/cost. Repeating observe_initial returns the same initial data, not new measurements.",
  "split_definition": "Train and test use independent parameter/noise draws from the same published distributions. No claim of out-of-family generalization.",
  "status": "Original synthetic prototype; no physical calibration or LLM training result.",
  "submission": "Submit one finite numeric matrix in the exact prediction_shape. Submission is terminal and cannot be retried after acceptance.",
  "scoring": {
    "name": "inverse_normalized_mse",
    "formula": "score = 1 / (1 + mean(((prediction - noiseless_hidden_target) / scale)^2))",
    "scale": [
      0.02
    ],
    "range": [
      0,
      1
    ],
    "meaning": "Higher is better. Exact latent-mean prediction scores 1. A normalized RMSE equal to one measurement-noise standard deviation scores 0.5. Measurement noise is not added to hidden targets."
  },
  "title": "Reaction mechanism identification",
  "outputs": [
    "concentration"
  ],
  "noise_std": [
    0.02
  ],
  "instructions": "Distinguish two idealized mass-conserving reaction mechanisms by choosing time/species assays under a three-credit budget. Predict the listed unmeasured early, middle and late time-course concentrations. Initial concentration and mechanism family are known; mechanism and rates are hidden.",
  "model": "Either sequential A -> B -> C with rates k1,k2, or parallel A -> B and A -> C with rates k1,k2. First-order irreversible kinetics, initial A=c and B=C=0; no physical calibration.",
  "prior": "Mechanism is equally likely. Rates k1,k2 independently log-Uniform(0.1,0.75), in inverse synthetic time units.",
  "initial_queries": [
    {
      "time": 0.5,
      "species": "A",
      "concentration": 1.0
    }
  ],
  "prediction_queries": [
    {
      "time": 0.4,
      "species": "A",
      "concentration": 1.0
    },
    {
      "time": 0.4,
      "species": "B",
      "concentration": 1.0
    },
    {
      "time": 0.4,
      "species": "C",
      "concentration": 1.0
    },
    {
      "time": 1.25,
      "species": "A",
      "concentration": 0.7
    },
    {
      "time": 1.25,
      "species": "B",
      "concentration": 0.7
    },
    {
      "time": 1.25,
      "species": "C",
      "concentration": 0.7
    },
    {
      "time": 3.5,
      "species": "A",
      "concentration": 1.0
    },
    {
      "time": 3.5,
      "species": "B",
      "concentration": 1.0
    },
    {
      "time": 3.5,
      "species": "C",
      "concentration": 1.0
    },
    {
      "time": 7.5,
      "species": "A",
      "concentration": 1.3
    },
    {
      "time": 7.5,
      "species": "B",
      "concentration": 1.3
    },
    {
      "time": 7.5,
      "species": "C",
      "concentration": 1.3
    },
    {
      "time": 10.0,
      "species": "A",
      "concentration": 1.0
    },
    {
      "time": 10.0,
      "species": "B",
      "concentration": 1.0
    },
    {
      "time": 10.0,
      "species": "C",
      "concentration": 1.0
    }
  ],
  "experiments": [
    {
      "id": "assay-A-0",
      "label": "Assay A at t=0.25",
      "query": {
        "time": 0.25,
        "species": "A",
        "concentration": 1.0
      },
      "cost": 1,
      "max_replicates": 2
    },
    {
      "id": "assay-B-0",
      "label": "Assay B at t=0.25",
      "query": {
        "time": 0.25,
        "species": "B",
        "concentration": 1.0
      },
      "cost": 1,
      "max_replicates": 2
    },
    {
      "id": "assay-C-0",
      "label": "Assay C at t=0.25",
      "query": {
        "time": 0.25,
        "species": "C",
        "concentration": 1.0
      },
      "cost": 1,
      "max_replicates": 2
    },
    {
      "id": "assay-A-1",
      "label": "Assay A at t=0.75",
      "query": {
        "time": 0.75,
        "species": "A",
        "concentration": 1.0
      },
      "cost": 1,
      "max_replicates": 2
    },
    {
      "id": "assay-B-1",
      "label": "Assay B at t=0.75",
      "query": {
        "time": 0.75,
        "species": "B",
        "concentration": 1.0
      },
      "cost": 1,
      "max_replicates": 2
    },
    {
      "id": "assay-C-1",
      "label": "Assay C at t=0.75",
      "query": {
        "time": 0.75,
        "species": "C",
        "concentration": 1.0
      },
      "cost": 1,
      "max_replicates": 2
    },
    {
      "id": "assay-A-2",
      "label": "Assay A at t=1.5",
      "query": {
        "time": 1.5,
        "species": "A",
        "concentration": 1.0
      },
      "cost": 1,
      "max_replicates": 2
    },
    {
      "id": "assay-B-2",
      "label": "Assay B at t=1.5",
      "query": {
        "time": 1.5,
        "species": "B",
        "concentration": 1.0
      },
      "cost": 1,
      "max_replicates": 2
    },
    {
      "id": "assay-C-2",
      "label": "Assay C at t=1.5",
      "query": {
        "time": 1.5,
        "species": "C",
        "concentration": 1.0
      },
      "cost": 1,
      "max_replicates": 2
    },
    {
      "id": "assay-A-3",
      "label": "Assay A at t=2.5",
      "query": {
        "time": 2.5,
        "species": "A",
        "concentration": 1.0
      },
      "cost": 1,
      "max_replicates": 2
    },
    {
      "id": "assay-B-3",
      "label": "Assay B at t=2.5",
      "query": {
        "time": 2.5,
        "species": "B",
        "concentration": 1.0
      },
      "cost": 1,
      "max_replicates": 2
    },
    {
      "id": "assay-C-3",
      "label": "Assay C at t=2.5",
      "query": {
        "time": 2.5,
        "species": "C",
        "concentration": 1.0
      },
      "cost": 1,
      "max_replicates": 2
    },
    {
      "id": "assay-A-4",
      "label": "Assay A at t=4",
      "query": {
        "time": 4.0,
        "species": "A",
        "concentration": 1.0
      },
      "cost": 1,
      "max_replicates": 2
    },
    {
      "id": "assay-B-4",
      "label": "Assay B at t=4",
      "query": {
        "time": 4.0,
        "species": "B",
        "concentration": 1.0
      },
      "cost": 1,
      "max_replicates": 2
    },
    {
      "id": "assay-C-4",
      "label": "Assay C at t=4",
      "query": {
        "time": 4.0,
        "species": "C",
        "concentration": 1.0
      },
      "cost": 1,
      "max_replicates": 2
    },
    {
      "id": "assay-A-5",
      "label": "Assay A at t=6",
      "query": {
        "time": 6.0,
        "species": "A",
        "concentration": 1.0
      },
      "cost": 1,
      "max_replicates": 2
    },
    {
      "id": "assay-B-5",
      "label": "Assay B at t=6",
      "query": {
        "time": 6.0,
        "species": "B",
        "concentration": 1.0
      },
      "cost": 1,
      "max_replicates": 2
    },
    {
      "id": "assay-C-5",
      "label": "Assay C at t=6",
      "query": {
        "time": 6.0,
        "species": "C",
        "concentration": 1.0
      },
      "cost": 1,
      "max_replicates": 2
    },
    {
      "id": "assay-A-6",
      "label": "Assay A at t=8",
      "query": {
        "time": 8.0,
        "species": "A",
        "concentration": 1.0
      },
      "cost": 1,
      "max_replicates": 2
    },
    {
      "id": "assay-B-6",
      "label": "Assay B at t=8",
      "query": {
        "time": 8.0,
        "species": "B",
        "concentration": 1.0
      },
      "cost": 1,
      "max_replicates": 2
    },
    {
      "id": "assay-C-6",
      "label": "Assay C at t=8",
      "query": {
        "time": 8.0,
        "species": "C",
        "concentration": 1.0
      },
      "cost": 1,
      "max_replicates": 2
    }
  ],
  "action_schema": {
    "type": "object",
    "properties": {
      "action_id": {
        "type": "string",
        "enum": [
          "assay-A-0",
          "assay-B-0",
          "assay-C-0",
          "assay-A-1",
          "assay-B-1",
          "assay-C-1",
          "assay-A-2",
          "assay-B-2",
          "assay-C-2",
          "assay-A-3",
          "assay-B-3",
          "assay-C-3",
          "assay-A-4",
          "assay-B-4",
          "assay-C-4",
          "assay-A-5",
          "assay-B-5",
          "assay-C-5",
          "assay-A-6",
          "assay-B-6",
          "assay-C-6"
        ]
      }
    },
    "required": [
      "action_id"
    ],
    "additionalProperties": false
  },
  "prediction_shape": [
    15,
    1
  ]
}