{
  "height": 83,
  "block_hash": "c960ea3dcec0bd6f1b6a37abb9ce52b31479d217c64488ae9305ea830719c8d1",
  "status": "confirmed",
  "bitcoin_block_height": 974883,
  "digest": {
    "alg": "sha256",
    "hex": "c960ea3dcec0bd6f1b6a37abb9ce52b31479d217c64488ae9305ea830719c8d1",
    "preimage": "block:{\"at\":\"2026-11-07T02:30:45.288Z\",\"entry_count\":1,\"first_seq\":184,\"height\":83,\"key_id\":\"key_a521921c2ba20669\",\"last_seq\":184,\"merkle_root\":\"b42c7e1c250f87255a077a848d784372db685d42684226e34e8f51b28ee808e9\",\"prev_hash\":\"af6b9e7bc5430e09665e82205a06facac72d262116b78b47a37478d01d7e8443\",\"v\":1}"
  },
  "calendars": [
    {
      "calendar": "https://a.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-11-07T02:38:43.467Z",
      "updated_at": "2026-11-07T04:38:43.483Z",
      "bitcoin_block_height": 974883,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://alice.btc.calendar.opentimestamps.org",
          "commitment": "6aee8f3508d434f4904ef2c9cc46d7e097afb2627ee2953a0560be7a25b731313a89292b8b3d2d04af8e05c5"
        },
        {
          "type": "bitcoin",
          "block_height": 974883,
          "merkle_root": "79abb9dd33baad0a1ff37045cc779f6fe1b133a7037999fbd2c996ad78e43b90"
        }
      ]
    },
    {
      "calendar": "https://b.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-11-07T02:38:43.467Z",
      "updated_at": "2026-11-07T04:38:43.483Z",
      "bitcoin_block_height": 974883,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://bob.btc.calendar.opentimestamps.org",
          "commitment": "6aee8f35aa76ee1b4cf6d921bdf5a440071009d481f867cf28c22ce5b758853628f0d1c1673e86e32f2e1910"
        },
        {
          "type": "bitcoin",
          "block_height": 974883,
          "merkle_root": "79abb9dd33baad0a1ff37045cc779f6fe1b133a7037999fbd2c996ad78e43b90"
        }
      ]
    },
    {
      "calendar": "https://finney.calendar.eternitywall.com",
      "status": "pending",
      "submitted_at": "2026-11-07T02:38:43.467Z",
      "updated_at": "2026-11-07T02:38:43.467Z",
      "bitcoin_block_height": null,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://finney.calendar.eternitywall.com",
          "commitment": "6aee8f35551f3304ed01f1a1ca06b99bdc583aba31022e62979944bbac05c1354e7451a119c6a6c603c4bf7a"
        }
      ]
    }
  ],
  "proof_url": "https://www.a2ally.com/v1/ledger/blocks/83/anchor.ots",
  "how_to_verify": "Download the .ots proof and run `ots verify -d <block_hash> <file>.ots` with the OpenTimestamps client, which checks the Bitcoin attestation against Bitcoin block headers. The digest is the block hash: sha256 of digest.preimage, the text \"block:\" followed by the canonical block header, which is the same header the issuer signs."
}