Get shard block proof

Returns a Merkle proof that links a shardchain block to a masterchain block. This proof cryptographically verifies that the shard block is part of the canonical chain. Essential for light clients and cross-chain bridges that need to verify shard data without trusting the API.

POST /api/v2/getShardBlockProof

Get shard block proof

cURL

curl --request POST \
  --url https://toncenter.com/api/v2/getShardBlockProof \
  --header 'Content-Type: application/json' \
  --header 'X-API-Key: <api-key>' \
  --data '
{
  "workchain": "<string>",
  "shard": "<string>",
  "seqno": "<string>",
  "from_seqno": "<string>"
}
'

200

{
  "ok": true,
  "result": {
    "@type": "blocks.shardBlockProof",
    "from": {
      "@type": "ton.blockIdExt",
      "workchain": 123,
      "shard": "<string>",
      "seqno": 123,
      "root_hash": "<string>",
      "file_hash": "<string>"
    },
    "mc_id": {
      "@type": "ton.blockIdExt",
      "workchain": 123,
      "shard": "<string>",
      "seqno": 123,
      "root_hash": "<string>",
      "file_hash": "<string>"
    },
    "links": [
      {
        "@type": "blocks.shardBlockLink",
        "id": {
          "@type": "ton.blockIdExt",
          "workchain": 123,
          "shard": "<string>",
          "seqno": 123,
          "root_hash": "<string>",
          "file_hash": "<string>"
        },
        "proof": "<string>"
      }
    ],
    "mc_proof": [
      {
        "@type": "blocks.blockLinkBack",
        "to_key_block": true,
        "from": {
          "@type": "ton.blockIdExt",
          "workchain": 123,
          "shard": "<string>",
          "seqno": 123,
          "root_hash": "<string>",
          "file_hash": "<string>"
        },
        "to": {
          "@type": "ton.blockIdExt",
          "workchain": 123,
          "shard": "<string>",
          "seqno": 123,
          "root_hash": "<string>",
          "file_hash": "<string>"
        },
        "dest_proof": "<string>",
        "proof": "<string>",
        "state_proof": "<string>"
      }
    ]
  },
  "@extra": "<string>"
}

Authorizations

APIKeyHeaderAPIKeyQuery

X-API-Key · string · header · required

Body

application/json

workchain · string integer<int32> · required

Workchain ID: -1 for masterchain, 0 for basechain. Most user transactions are on workchain 0.

shard · string integer<int64> · required

Shard identifier. A signed 64-bit integer. Masterchain uses -9223372036854775808.

seqno · string integer<int32> · required

Block or wallet sequence number. For blocks, this is the block height. For wallets, increment this for each outgoing transaction.

from_seqno · string integer<int32>

Starting masterchain block for proof generation.

Response

200

application/json

OK

Response containing Merkle proof linking shard block to masterchain.

ok · boolean · default: true · required

Indicates if the request succeeded. If false, check the error field for details.

result · object · required

The response data. Only present when ok is true.

Show child attributes

@extra · string

Optional request ID that you can pass in the request and receive back in the response. Useful for matching async responses.