{
  "metadata": {
    "experimentName": "Ball Comparison Example",
    "description": "Participants compare the apparent size of two circles.",
    "paperDOI": "https://doi.org/10.0000/coggym.example",
    "taskType": ["Visual Perception"],
    "responseType": ["multi-choice"],
    "contributors": ["CogGym Documentation Team"],
    "paper-title": "A Demonstration of Build-time Trial Expansion",
    "citation": "CogGym Documentation Team (2026). A Demonstration of Build-time Trial Expansion.",
    "year": 2026,
    "authors": ["CogGym Documentation Team"],
    "alias": "ball-comparison-build-example",
    "trial_presentation": "independent",
    "metadata": {
      "authoring_format": "eml-v1.5-trial-units"
    }
  },
  "trial_layout_config": {
    "layout": "2-columns",
    "default_width": ["45%", "45%"]
  },
  "instructions": [
    {
      "id": "instruction_01",
      "type": "instruction",
      "text": "<p>Compare the two circles and select which appears larger.</p>"
    }
  ],
  "trial_units": [
    {
      "id": "trial_1",
      "model_card": {
        "name": "Apparent circle-size comparison",
        "version": "1.0.0",
        "description": "Presents one circle-comparison condition and asks which circle appears larger.",
        "intended_use": "Build concrete visual-perception trials for the documentation example.",
        "provenance": {
          "source": "CogGym EML v1.5 documentation example",
          "license": "CC BY 4.0"
        },
        "contract": {
          "stimulus": "one named condition from each stimulus definition",
          "query": "one or more named response objects",
          "feedback": "optional static post-response content"
        }
      },
      "stimuli": {
        "stimulus_1": {
          "base": {
            "input_type": "text",
            "text": "The blue and red circles appear equal in size."
          },
          "variant_1": {
            "input_type": "text",
            "text": "The blue circle appears larger than the red circle."
          },
          "variant_2": {
            "input_type": "text",
            "text": "The red circle appears larger than the blue circle."
          }
        }
      },
      "queries": {
        "query_1": {
          "prompt": "Which circle appears larger?",
          "type": "multi-choice",
          "tag": "circle_size",
          "option": ["Blue", "Red", "Equal"],
          "randomize_order": false,
          "required": true
        }
      },
      "generation": {
        "vary": [
          {
            "stimulus": "stimulus_1",
            "conditions": ["base", "variant_1", "variant_2"]
          }
        ],
        "queries": ["query_1"],
        "id_template": "{unit}_{stimulus_1}"
      },
      "feedback": {
        "type": "text",
        "content": "Your response has been recorded.",
        "continue_label": "Continue"
      }
    }
  ],
  "sequencing": {
    "conditions": [
      {
        "condition": "all_variants",
        "prefix": ["instruction_01"],
        "sequences": [
          {
            "seq_id": "seq_forward",
            "units": ["trial_1"],
            "order": "generated",
            "block_size": 3
          },
          {
            "seq_id": "seq_reverse",
            "units": ["trial_1"],
            "order": "reverse",
            "block_size": 3
          }
        ]
      }
    ]
  }
}