{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "$id": "https://cognitivedelivery.co.uk/contract/1.0.0/audit-event.schema.json",
  "title": "CDF governance audit event",
  "description": "One line of the append-only governance journal. Rotated files carry the same shape. Deliberately holds a request hash rather than the request, and a sanitised summary rather than content: this file is retained indefinitely, so anything that reaches it is effectively permanent. CORRECTED against real artefacts: event_id and session_id are NOT required. A writer active between 2026-05-12 and 2026-05-15 emitted 61 codex.health.audit_probe records without them. The journal is append-only and retained indefinitely, so those records are permanent and a conformant reader will meet them. Rejecting real evidence would be worse than a slightly weaker schema. The current writer emits both.",
  "type": "object",
  "required": [
    "schema_version",
    "timestamp",
    "event_type"
  ],
  "properties": {
    "schema_version": {
      "type": "string"
    },
    "timestamp": {
      "type": "string",
      "pattern": "^\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}(\\.\\d+)?(Z|[+-]\\d{2}:\\d{2})$",
      "description": "ISO 8601 with a timezone."
    },
    "event_id": {
      "type": "string",
      "description": "Optional for historical reasons only \u2014 see the schema description. Current writers emit it."
    },
    "event_type": {
      "type": "string",
      "description": "OPEN, unlike the CDI signal vocabulary. The journal records what happened; a product may record its own kinds of event."
    },
    "session_id": {
      "type": "string",
      "description": "Optional for historical reasons only \u2014 see the schema description. Current writers emit it."
    },
    "request_id": {
      "type": "string"
    },
    "spec_slug": {
      "type": "string"
    },
    "task_id": {
      "type": "string"
    },
    "phase": {
      "type": "string",
      "description": "An OPEN string. This field previously carried a closed six-value software lifecycle union, which meant a product with a different lifecycle could not record its own phase in the shared journal without lying. A reader must tolerate an unrecognised value: not throw, not coerce it to a known one, not drop it."
    },
    "actor": {
      "type": "object",
      "description": "Who or what acted. Records the KIND of actor and the model, never a person's name, email or git identity.",
      "required": [
        "kind"
      ],
      "properties": {
        "kind": {
          "type": "string",
          "enum": [
            "human",
            "agent",
            "system"
          ]
        },
        "runtime": {
          "type": "string"
        },
        "model_vendor": {
          "type": "string"
        },
        "model_family": {
          "type": "string"
        },
        "model_version": {
          "type": "string"
        }
      },
      "additionalProperties": true
    },
    "summary": {
      "type": "string"
    },
    "reasoning": {
      "type": "string"
    },
    "request_hash": {
      "type": "string",
      "description": "SHA-256 of the request. NEVER the request itself."
    },
    "outcome": {
      "type": "string",
      "enum": [
        "success",
        "failure",
        "partial"
      ]
    },
    "details": {
      "type": "object",
      "description": "Sanitised before write: keys matching token, secret, password, authorization, prompt, content, file or path are dropped. Do not defeat this by renaming a sensitive field.",
      "additionalProperties": {
        "type": [
          "string",
          "number",
          "boolean"
        ]
      }
    }
  },
  "additionalProperties": true
}