fyi.opensocial.describePush

{
  "$type": "com.atproto.lexicon.schema",
  "defs": {
    "main": {
      "description": "How this host sends alerts to people's devices (Web Push): the key a browser subscribes with, and, to someone signed in, how many of their devices it alerts.",
      "output": {
        "encoding": "application/json",
        "schema": {
          "properties": {
            "devices": {
              "description": "To the caller, signed in: how many of their devices get alerts.",
              "minimum": 0,
              "type": "integer"
            },
            "publicKey": {
              "description": "The host's VAPID public key, base64url.",
              "type": "string"
            }
          },
          "required": [
            "publicKey"
          ],
          "type": "object"
        }
      },
      "type": "query"
    }
  },
  "id": "fyi.opensocial.describePush",
  "lexicon": 1
}