# blockSubscribe Subscribe to receive notification anytime a new block is `confirmed` or `finalized`. {% hint style="danger" %} **Unstable Method** This subscription is considered **unstable** and is only available if the validator was started with the `--rpc-pubsub-enable-block-subscription` flag. The format of this subscription may change in the future. {% endhint %} #### Parameters required for this RPC call * filter criteria for the logs to receive results by account type; currently supported: * `all` - include all transactions in block * A JSON object with the following field: * `mentionsAccountOrProgram: ` - return only transactions that mention the provided public key (as base-58 encoded string). If no mentions in a given block, then no notification will be sent. * **configuration object**: This contains the following parameters, all are optional fields. * **commitment**: The commitment describes how finalized a block is at that point in time. Commitment levels processed, confirmed and finalized are supported, defaults to finalized. * **encoding**: Encoding format for Account data * `base58` is slow. * `jsonParsed` encoding attempts to use program-specific state parsers to return more human-readable and explicit account state data * If `jsonParsed` is requested but a parser cannot be found, the field falls back to binary encoding, detectable when the `data` field is type `string`. * Supports: `base58` , `base64` , `base64+zstd` , `jsonParsed` * **transactionDetails**: The level of transaction detail to return * If `accounts` are requested, transaction details only include signatures and an annotated list of accounts in each transaction. * Transaction metadata is limited to only: fee, err, pre\_balances, post\_balances, pre\_token\_balances, and post\_token\_balances. * maxSupportedTransactionVersion: Currently, the only valid value for this parameter is `0`. Setting it to `0` allows you to fetch all transactions, including both Versioned and legacy transactions. This parameter determines the maximum transaction version that will be returned in the response. If you request a transaction with a higher version than this value, an error will be returned. If you omit this parameter, only legacy transactions will be returned—any versioned transaction will result in an error. * showRewards: Whether to populate the `rewards` array. If parameter not provided, the default includes rewards. This is a boolean field. {% tabs %} {% tab title="Websocket" %} ```json { "jsonrpc": "2.0", "id": "1", "method": "blockSubscribe", "params": [ { "mentionsAccountOrProgram": "LieKvPRE8XeX3Y2xVNHjKlpAScD12lYySBVQ4HqoJ5op" }, { "commitment": "confirmed", "encoding": "base64", "transactionDetails": "full", "maxSupportedTransactionVersion": 0, "showRewards": true } ] } ``` {% endtab %} {% tab title="Response" %} ```json { "jsonrpc": "2.0", "result": 0, // id required to unsubscribe "id": 1 } ``` {% endtab %} {% endtabs %} **Notification Format:** The notification will be an object with the following fields: * `slot: ` - The corresponding slot. * `err: ` - Error if something went wrong publishing the notification otherwise null. * `block: ` - A block object as seen in the [getBlock](https://solana.com/docs/rpc/http/getblock) RPC HTTP method. {% tabs %} {% tab title="Notification Format" %} ```json { "jsonrpc": "2.0", "method": "blockNotification", "params": { "result": { "context": { "slot": 112301554 }, "value": { "slot": 112301554, "block": { "previousBlockhash": "GJp125YAN4ufCSUvZJVdCyWQJ7RPWMmwxoyUQySydZA", "blockhash": "6ojMHjctdqfB55JDpEpqfHnP96fiaHEcvzEQ2NNcxzHP", "parentSlot": 112301553, "transactions": [ { "transaction": [ "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", "base64" ], "meta": { "err": null, "status": { "Ok": null }, "fee": 5000, "preBalances": [ 1758510880, 2067120, 1566000, 1461600, 2039280, 2039280, 1900080, 1865280, 0, 3680844220, 2039280 ], "postBalances": [ 1758505880, 2067120, 1566000, 1461600, 2039280, 2039280, 1900080, 1865280, 0, 3680844220, 2039280 ], "innerInstructions": [ { "index": 0, "instructions": [ { "programIdIndex": 13, "accounts": [1, 15, 3, 4, 2, 14], "data": "21TeLgZXNbtHXVBzCaiRmH" }, { "programIdIndex": 14, "accounts": [3, 4, 1], "data": "6qfC8ic7Aq99" }, { "programIdIndex": 13, "accounts": [1, 15, 3, 5, 2, 14], "data": "21TeLgZXNbsn4QEpaSEr3q" }, { "programIdIndex": 14, "accounts": [3, 5, 1], "data": "6LC7BYyxhFRh" } ] }, { "index": 1, "instructions": [ { "programIdIndex": 14, "accounts": [4, 3, 0], "data": "7aUiLHFjSVdZ" }, { "programIdIndex": 19, "accounts": [17, 18, 16, 9, 11, 12, 14], "data": "8kvZyjATKQWYxaKR1qD53V" }, { "programIdIndex": 14, "accounts": [9, 11, 18], "data": "6qfC8ic7Aq99" } ] } ], "logMessages": [ "Program QMNeHCGYnLVDn1icRAfQZpjPLBNkfGbSKRB83G5d8KB invoke [1]", "Program QMWoBmAyJLAsA1Lh9ugMTw2gciTihncciphzdNzdZYV invoke [2]" ], "preTokenBalances": [ { "accountIndex": 4, "mint": "iouQcQBAiEXe6cKLS85zmZxUqaCqBdeHFpqKoSz615u", "uiTokenAmount": { "uiAmount": null, "decimals": 6, "amount": "0", "uiAmountString": "0" }, "owner": "LieKvPRE8XeX3Y2xVNHjKlpAScD12lYySBVQ4HqoJ5op", "programId": "TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA" }, { "accountIndex": 5, "mint": "iouQcQBAiEXe6cKLS85zmZxUqaCqBdeHFpqKoSz615u", "uiTokenAmount": { "uiAmount": 11513.0679, "decimals": 6, "amount": "11513067900", "uiAmountString": "11513.0679" }, "owner": "rXhAofQCT7NN9TUqigyEAUzV1uLL4boeD8CRkNBSkYk", "programId": "TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA" }, { "accountIndex": 10, "mint": "Saber2gLauYim4Mvftnrasomsv6NvAuncvMEZwcLpD1", "uiTokenAmount": { "uiAmount": null, "decimals": 6, "amount": "0", "uiAmountString": "0" }, "owner": "CL9wkGFT3SZRRNa9dgaovuRV7jrVVigBUZ6DjcgySsCU", "programId": "TokenzQdBNbLqP5VEhdkAS6EPFLC1PHnBqCXEpPxuEb" }, { "accountIndex": 11, "mint": "Saber2gLauYim4Mvftnrasomsv6NvAuncvMEZwcLpD1", "uiTokenAmount": { "uiAmount": 15138.514093, "decimals": 6, "amount": "15138514093", "uiAmountString": "15138.514093" }, "owner": "LieKvPRE8XeX3Y2xVNHjKlpAScD12lYySBVQ4HqoJ5op", "programId": "TokenzQdBNbLqP5VEhdkAS6EPFLC1PHnBqCXEpPxuEb" } ], "postTokenBalances": [ { "accountIndex": 4, "mint": "iouQcQBAiEXe6cKLS85zmZxUqaCqBdeHFpqKoSz615u", "uiTokenAmount": { "uiAmount": null, "decimals": 6, "amount": "0", "uiAmountString": "0" }, "owner": "LieKvPRE8XeX3Y2xVNHjKlpAScD12lYySBVQ4HqoJ5op", "programId": "TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA" }, { "accountIndex": 5, "mint": "iouQcQBAiEXe6cKLS85zmZxUqaCqBdeHFpqKoSz615u", "uiTokenAmount": { "uiAmount": 11513.103028, "decimals": 6, "amount": "11513103028", "uiAmountString": "11513.103028" }, "owner": "rXhAofQCT7NN9TUqigyEAUzV1uLL4boeD8CRkNBSkYk", "programId": "TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA" }, { "accountIndex": 10, "mint": "Saber2gLauYim4Mvftnrasomsv6NvAuncvMEZwcLpD1", "uiTokenAmount": { "uiAmount": null, "decimals": 6, "amount": "0", "uiAmountString": "0" }, "owner": "CL9wkGFT3SZRRNa9dgaovuRV7jrVVigBUZ6DjcgySsCU", "programId": "TokenzQdBNbLqP5VEhdkAS6EPFLC1PHnBqCXEpPxuEb" }, { "accountIndex": 11, "mint": "Saber2gLauYim4Mvftnrasomsv6NvAuncvMEZwcLpD1", "uiTokenAmount": { "uiAmount": 15489.767829, "decimals": 6, "amount": "15489767829", "uiAmountString": "15489.767829" }, "owner": "BeiHVPRE8XeX3Y2xVNrSsTpAScH94nYySBVQ4HqgN9at", "programId": "TokenzQdBNbLqP5VEhdkAS6EPFLC1PHnBqCXEpPxuEb" } ], "rewards": [] } } ], "blockTime": 1639926816, "blockHeight": 101210751 }, "err": null } }, "subscription": 14 } } ``` {% endtab %} {% endtabs %} --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.shyft.to/solana/rpc-calls/solana-websockets/blocksubscribe.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.