{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://lems.ai/event-schema.json",
  "title": "LEMs Forecast Context v1",
  "description": "A typed, time-ordered evidence packet for constrained forecasts. Past same-type events are the direct analogue set; adjacent events provide relevant exogenous context. Do not include information that was not observable at forecast_time.",
  "type": "object",
  "additionalProperties": false,
  "required": ["schema_version", "forecast", "same_type_events", "adjacent_events"],
  "properties": {
    "schema_version": {"const": "lems.forecast-context.v1"},
    "forecast": {
      "type": "object",
      "additionalProperties": false,
      "required": ["event_type", "forecast_time", "target_time", "question", "output"],
      "properties": {
        "event_type": {"type": "string", "description": "Stable namespace, e.g. finance.bond_trade_price or sports.game_winner."},
        "forecast_time": {"type": "string", "format": "date-time", "description": "Information cutoff. Every source_event time must be at or before this timestamp."},
        "target_time": {"type": "string", "format": "date-time"},
        "question": {"type": "string", "maxLength": 10000},
        "output": {"$ref": "#/$defs/outputSpec"},
        "reasoning": {"type": "boolean", "default": false, "description": "Requests a separate hidden deliberation pass when the deployed model supports it; the constrained final output remains the only returned completion."}
      }
    },
    "same_type_events": {
      "type": "array",
      "description": "Historical events matching forecast.event_type. Keep the raw fields, outcome and source provenance needed to establish an analogue set.",
      "items": {"$ref": "#/$defs/event"}
    },
    "adjacent_events": {
      "type": "array",
      "description": "Relevant contemporaneous but different event types: market moves, scheduled releases, team injuries, polling, etc. They must be available before forecast_time.",
      "items": {"$ref": "#/$defs/event"}
    },
    "assumptions": {"type": "array", "items": {"type": "string"}},
    "provenance": {"type": "object", "additionalProperties": {"type": "string"}, "description": "Dataset identifiers, query hashes, or source URLs. Never send credentials or private identifiers."}
  },
  "$defs": {
    "event": {
      "type": "object",
      "additionalProperties": false,
      "required": ["event_id", "event_type", "observed_at", "fields"],
      "properties": {
        "event_id": {"type": "string"},
        "event_type": {"type": "string"},
        "observed_at": {"type": "string", "format": "date-time"},
        "available_at": {"type": "string", "format": "date-time", "description": "When this fact became knowable. Must be <= forecast.forecast_time."},
        "fields": {"type": "object", "additionalProperties": true},
        "outcome": {"type": ["object", "string", "number", "boolean", "null"]},
        "source": {"type": "string"}
      }
    },
    "outputSpec": {
      "oneOf": [
        {"type": "object", "additionalProperties": false, "required": ["kind", "values"], "properties": {"kind": {"const": "categorical"}, "values": {"type": "array", "minItems": 1, "maxItems": 100, "items": {"type": "string", "minLength": 1}}}},
        {"type": "object", "additionalProperties": false, "required": ["kind"], "properties": {"kind": {"const": "binary"}}},
        {"type": "object", "additionalProperties": false, "required": ["kind", "minimum", "maximum"], "properties": {"kind": {"const": "int"}, "minimum": {"type": "integer"}, "maximum": {"type": "integer"}, "increment": {"type": "integer", "minimum": 1, "default": 1}}},
        {"type": "object", "additionalProperties": false, "required": ["kind", "minimum", "maximum", "precision", "scientific"], "properties": {"kind": {"const": "float"}, "minimum": {"type": "string", "pattern": "^-?[0-9]+(\\.[0-9]+)?$"}, "maximum": {"type": "string", "pattern": "^-?[0-9]+(\\.[0-9]+)?$"}, "increment": {"type": ["string", "null"]}, "precision": {"type": "integer", "minimum": 0, "maximum": 12}, "scientific": {"type": "boolean"}}}
      ]
    }
  }
}