{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "title": "Health report format, version 1",
  "description": "What a service serves so that a health endpoint monitor can show its state, the rules that decided it, and the evidence. See health-format.md for how each field is read.",
  "type": "object",
  "required": ["healthReport", "status"],
  "properties": {
    "healthReport": {
      "description": "Format version. Also how the document is recognised.",
      "const": 1
    },
    "status": { "$ref": "#/$defs/status" },
    "message": {
      "description": "One line saying what is wrong. The first 200 characters are shown.",
      "type": "string"
    },
    "checkedAt": { "$ref": "#/$defs/timestamp" },
    "service": { "description": "Which service wrote this. The first 60 characters are shown.", "type": "string" },
    "version": { "description": "The running build. The first 40 characters are shown.", "type": "string" },
    "environment": { "description": "production, staging, and so on. The first 40 characters are shown.", "type": "string" },
    "components": {
      "description": "The parts that make up the verdict, in display order. The first 50 are shown.",
      "type": "array",
      "items": { "$ref": "#/$defs/component" }
    }
  },
  "$defs": {
    "status": {
      "description": "up, degraded or down. Readers also accept ok, pass, healthy, warn, warning, fail, error and unhealthy in any case; this schema accepts only the canonical three so that new endpoints use them.",
      "enum": ["up", "degraded", "down"]
    },
    "timestamp": {
      "description": "RFC 3339 date and time with an offset, for example 2026-10-09T14:02:11Z.",
      "type": "string",
      "pattern": "^\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}(\\.\\d{1,9})?(Z|[+-]\\d{2}:\\d{2})$"
    },
    "id": {
      "description": "Stable identifier. Never change it once shipped.",
      "type": "string",
      "pattern": "^[A-Za-z0-9._-]{1,64}$"
    },
    "component": {
      "type": "object",
      "required": ["id", "status"],
      "properties": {
        "id": { "$ref": "#/$defs/id" },
        "name": { "description": "Display name, defaults to id. The first 60 characters are shown.", "type": "string" },
        "status": { "$ref": "#/$defs/status" },
        "message": { "description": "What is wrong with this part, or a short reading. The first 200 characters are shown.", "type": "string" },
        "since": { "$ref": "#/$defs/timestamp" },
        "value": { "type": "number" },
        "unit": { "description": "Printed after value. The first 16 characters are shown.", "type": "string" },
        "durationMs": { "description": "How long this part's own check took.", "type": "number", "minimum": 0 },
        "conditions": {
          "description": "The rules that decided this part's status. The first 20 are shown.",
          "type": "array",
          "items": { "$ref": "#/$defs/condition" }
        },
        "log": {
          "description": "What happened, newest last. The first 50 are shown.",
          "type": "array",
          "items": { "$ref": "#/$defs/logEntry" }
        }
      }
    },
    "condition": {
      "type": "object",
      "required": ["id", "status"],
      "properties": {
        "id": { "$ref": "#/$defs/id" },
        "name": { "description": "Display name, defaults to id. The first 60 characters are shown.", "type": "string" },
        "status": { "$ref": "#/$defs/status" },
        "observed": { "description": "What was measured. Strings are cut to 80 characters.", "anyOf": [{ "type": "number" }, { "type": "string" }, { "type": "boolean" }] },
        "rule": { "description": "The threshold, in words. The first 80 characters are shown.", "type": "string" },
        "unit": { "description": "Printed after observed. The first 16 characters are shown.", "type": "string" },
        "window": { "description": "The span the measurement covers, such as 5m. The first 16 characters are shown.", "type": "string" },
        "message": { "description": "The first 200 characters are shown.", "type": "string" }
      }
    },
    "logEntry": {
      "type": "object",
      "required": ["at", "level", "message"],
      "properties": {
        "at": { "$ref": "#/$defs/timestamp" },
        "level": { "enum": ["info", "warn", "error"] },
        "message": { "description": "The first 500 characters are shown.", "type": "string" },
        "data": {
          "description": "Flat key and value pairs. The first 20 keys are shown; strings are cut to 200 characters.",
          "type": "object",
          "additionalProperties": { "anyOf": [{ "type": "string" }, { "type": "number" }, { "type": "boolean" }, { "type": "null" }] }
        }
      }
    }
  }
}