{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "kei-artifact://spec",
  "title": "Agent Specification",
  "description": "Architect output — what to build and under which constraints.",
  "type": "object",
  "additionalProperties": false,
  "required": ["goal", "constraints", "invariants"],
  "properties": {
    "goal": {
      "type": "string",
      "minLength": 1
    },
    "constraints": {
      "type": "array",
      "items": {"type": "string", "minLength": 1}
    },
    "invariants": {
      "type": "array",
      "items": {"type": "string", "minLength": 1}
    },
    "tradeoffs": {
      "type": "array",
      "items": {
        "type": "object",
        "additionalProperties": false,
        "required": ["choice", "rejected", "because"],
        "properties": {
          "choice": {"type": "string", "minLength": 1},
          "rejected": {"type": "string", "minLength": 1},
          "because": {"type": "string", "minLength": 1}
        }
      }
    },
    "evidence_grade": {
      "type": "string",
      "enum": ["E1", "E2", "E3", "E4", "E5", "E6"]
    }
  }
}