{
  "type": "object",
  "properties": {
    "nct_id": {
      "type": "string",
      "description": "The ClinicalTrials.gov identifier for this trial (echo it back verbatim)."
    },
    "compound": {
      "type": "string",
      "description": "The primary drug/agent under test, taken from the trial's interventions. 'unknown' if no investigational agent is identifiable (e.g. a device or behavioral trial)."
    },
    "targeting_mechanism": {
      "type": "string",
      "description": "One sentence: the molecular target and mechanism of action. May be drawn from the trial summary itself OR a provided paper passage. 'unknown' if neither states it."
    },
    "targeting_mechanism_pmid": {
      "type": "string",
      "description": "PMID of the supporting passage from the EVIDENCE list, if the mechanism came from a paper. Empty string if it came from the trial summary itself or is unknown."
    },
    "animal_results": {
      "type": "string",
      "description": "Preclinical / animal-model efficacy findings for this compound. MUST be supported by a passage in the provided EVIDENCE list. 'unknown' if no provided passage reports animal/preclinical results — do NOT use outside knowledge."
    },
    "animal_results_pmid": {
      "type": "string",
      "description": "PMID from the EVIDENCE list supporting animal_results. Empty string only when animal_results is 'unknown'."
    },
    "repurposed_from": {
      "type": "string",
      "description": "If this is a repurposed drug, its original approved indication (e.g. 'type 2 diabetes'), supported by a provided EVIDENCE passage. 'not repurposed' for agents developed de novo for ALS/neurodegeneration. 'unknown' if no provided passage establishes an original indication — do NOT use outside knowledge."
    },
    "repurposed_from_pmid": {
      "type": "string",
      "description": "PMID from the EVIDENCE list supporting repurposed_from. Empty string when repurposed_from is 'not repurposed' or 'unknown'."
    }
  },
  "required": [
    "nct_id",
    "compound",
    "targeting_mechanism",
    "targeting_mechanism_pmid",
    "animal_results",
    "animal_results_pmid",
    "repurposed_from",
    "repurposed_from_pmid"
  ]
}