{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://understand-quickly.dev/schemas/meta.schema.json",
  "type": "object",
  "required": ["schema_version", "generated_at", "entries"],
  "additionalProperties": false,
  "properties": {
    "schema_version": { "const": 1 },
    "generated_at": { "type": "string", "format": "date-time" },
    "last_drift_index": {
      "type": ["integer", "null"],
      "minimum": 0,
      "description": "Rotating cursor into entries[] for the per-run drift-detection budget. sync.mjs processes a soft cap of entries per run starting at this index and writes back the next index so successive runs cover the whole registry."
    },
    "entries": {
      "type": "array",
      "items": { "$ref": "#/$defs/entry" }
    }
  },
  "$defs": {
    "entry": {
      "type": "object",
      "required": ["id", "owner", "repo", "format", "graph_url", "description"],
      "additionalProperties": false,
      "properties": {
        "id": { "type": "string", "pattern": "^[A-Za-z0-9_.-]+/[A-Za-z0-9_.-]+$" },
        "owner": { "type": "string", "minLength": 1, "maxLength": 100, "pattern": "^[A-Za-z0-9_.-]+$" },
        "repo": { "type": "string", "minLength": 1, "maxLength": 100, "pattern": "^[A-Za-z0-9_.-]+$" },
        "default_branch": { "type": "string", "default": "main" },
        "format": { "type": "string", "pattern": "^[a-z0-9-]+@[0-9]+$" },
        "graph_url": { "type": "string", "format": "uri", "pattern": "^https://" },
        "description": { "type": "string", "maxLength": 200 },
        "tags": { "type": "array", "items": { "type": "string" }, "default": [] },
        "added_at": { "type": "string", "format": "date-time" },
        "last_synced": { "type": ["string", "null"], "format": "date-time" },
        "last_sha": { "type": ["string", "null"], "pattern": "^[a-f0-9]{64}$" },
        "size_bytes": { "type": ["integer", "null"], "minimum": 0 },
        "status": {
          "type": "string",
          "enum": ["ok", "missing", "invalid", "oversize", "transient_error", "dead", "renamed", "revoked"],
          "default": "ok",
          "description": "Lifecycle status. `revoked` is a maintainer-only state for entries that have been intentionally retracted; agents MUST NOT consume revoked entries, and sync skips fetch + leaves the entry untouched."
        },
        "last_error": { "type": ["string", "null"] },
        "miss_count": { "type": "integer", "minimum": 0, "default": 0 },
        "renamed_to": { "type": ["string", "null"], "pattern": "^[A-Za-z0-9_.-]+/[A-Za-z0-9_.-]+$" },
        "nodes_count": { "type": "integer", "minimum": 0 },
        "edges_count": { "type": "integer", "minimum": 0 },
        "top_kinds": {
          "type": "array",
          "maxItems": 10,
          "items": {
            "type": "object",
            "required": ["kind", "count"],
            "additionalProperties": false,
            "properties": {
              "kind": { "type": "string", "minLength": 1 },
              "count": { "type": "integer", "minimum": 0 }
            }
          }
        },
        "languages": {
          "type": "array",
          "maxItems": 10,
          "items": { "type": "string", "minLength": 1 }
        },
        "source_sha": {
          "type": ["string", "null"],
          "pattern": "^[a-f0-9]{40}$",
          "description": "40-hex sha of the source commit the graph was generated against. Producer-supplied (sniffed from graph metadata) — never set automatically by sync."
        },
        "head_sha": {
          "type": ["string", "null"],
          "pattern": "^[a-f0-9]{40}$",
          "description": "Latest 40-hex sha on the source repo's default branch at sync time. null when drift detection was skipped or failed."
        },
        "commits_behind": {
          "type": ["integer", "null"],
          "minimum": 0,
          "description": "Number of commits between source_sha and head_sha. 0 means up-to-date, null means drift detection was skipped or failed."
        },
        "drift_checked_at": {
          "type": ["string", "null"],
          "format": "date-time",
          "description": "ISO-8601 timestamp of the last drift-detection attempt, set whether the attempt succeeded or not."
        }
      }
    }
  }
}