{
  "height": 87,
  "block_hash": "f185bc791594f6360ea4641125bbd8b3158363646ce1f5fc20d46f2d31afefe4",
  "status": "confirmed",
  "bitcoin_block_height": 974883,
  "digest": {
    "alg": "sha256",
    "hex": "f185bc791594f6360ea4641125bbd8b3158363646ce1f5fc20d46f2d31afefe4",
    "preimage": "block:{\"at\":\"2026-11-07T02:40:45.315Z\",\"entry_count\":1,\"first_seq\":190,\"height\":87,\"key_id\":\"key_a521921c2ba20669\",\"last_seq\":190,\"merkle_root\":\"1b9b15c800e130e3e189a80ffd4d2644b8d97a2fe07066696c247bdc24bc9c90\",\"prev_hash\":\"c0b7271eeab33d7c12e538a4c28297729e64c6d285d3bc83b5ff8b110e2135e1\",\"v\":1}"
  },
  "calendars": [
    {
      "calendar": "https://a.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-11-07T02:48:43.467Z",
      "updated_at": "2026-11-07T04:48:43.485Z",
      "bitcoin_block_height": 974883,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://alice.btc.calendar.opentimestamps.org",
          "commitment": "6aee918d9189477f6bb55778f14c1ccc757372150f49ab0a25d50ff4aba97cc59bf28a15119d36ddfad64c70"
        },
        {
          "type": "bitcoin",
          "block_height": 974883,
          "merkle_root": "79abb9dd33baad0a1ff37045cc779f6fe1b133a7037999fbd2c996ad78e43b90"
        }
      ]
    },
    {
      "calendar": "https://b.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-11-07T02:48:43.467Z",
      "updated_at": "2026-11-07T04:48:43.485Z",
      "bitcoin_block_height": 974883,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://bob.btc.calendar.opentimestamps.org",
          "commitment": "6aee918dc72604e6efbff9e11bbb851acca13dacf9dad0c252c8934e7b2b195722eb1c4a98dd729670c4fb41"
        },
        {
          "type": "bitcoin",
          "block_height": 974883,
          "merkle_root": "79abb9dd33baad0a1ff37045cc779f6fe1b133a7037999fbd2c996ad78e43b90"
        }
      ]
    },
    {
      "calendar": "https://finney.calendar.eternitywall.com",
      "status": "pending",
      "submitted_at": "2026-11-07T02:48:43.467Z",
      "updated_at": "2026-11-07T02:48:43.467Z",
      "bitcoin_block_height": null,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://finney.calendar.eternitywall.com",
          "commitment": "6aee918d13bfe375c6a71d653c1fa0d2dbff1f761cc50e9c542e744e539585ddb8f1be21671ed36b95bd3623"
        }
      ]
    }
  ],
  "proof_url": "https://www.a2ally.com/v1/ledger/blocks/87/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."
}