Block headers
Provides block headers without the payload, each time a new block appears on the blockchain.
Example Request
Started from latest block:
_10{_10    "subscription_id": "some-id",_10    "action": "subscribe",_10    "topic": "block_headers",_10    "arguments": {_10        "block_status": "finalized"_10    }_10}
Started from block height 106195326:
_10{_10    "subscription_id": "some-id",_10    "action": "subscribe",_10    "topic": "block_headers",_10    "arguments": {_10        "block_status": "finalized",_10        "start_block_height": "106195326"_10    }_10}
Started from block id cb27b014fa105a1e0e64d56cfbe2d7e140f4adf32938e38c3459592d01a72e91:
_10{_10    "subscription_id": "some-id",_10    "action": "subscribe",_10    "topic": "block_headers",_10    "arguments": {_10        "block_status": "finalized",_10        "start_block_id": "cb27b014fa105a1e0e64d56cfbe2d7e140f4adf32938e38c3459592d01a72e91"_10    }_10}
Request Arguments
| Name | Type | Required | Description | 
|---|---|---|---|
block_status | STRING | YES | The status of blocks to subscribe to. Supported values are: sealed, finalized. | 
start_block_id | STRING | NO | The ID of the block from which the subscription starts. If this argument is set, it is not possible to set start_block_height. | 
start_block_height | STRING | NO | The height of the block from which the subscription starts. If this argument is set, it is not possible to set start_block_id | 
If neither start_block_id nor start_block_height is set, the subscription will start from the latest block based on its status.
Example Response
_11{_11    "subscription_id": "some-id",_11    "topic": "block_headers",_11    "payload": {_11        "id": "5cd0b1d0a0f0017c25647a6e2454a59aafa90682f2329449a610e19673ba07de",_11        "parent_id": "72ecd7cf6b18488b3597e677c5fa620d2dfad981fdd81b5cdb1851490b0cff56",_11        "height": "106195236",_11        "timestamp": "2025-03-11T12:18:39.702990376Z",_11        "parent_voter_signature": "+GyIAAAAAAAAAACwsabEiORFcP/ru95TABxwxXsxnUtJNoUbGB1xKKNtpR/LNUqDL5TyIQjL3xBl5KtKgLCFde8F5DHtUSGYSQUzaGhv+IoQgh1wgbXlY/soY5T30/HwmrucwD925EKOJAQUj7s="_11    }_11}