gRPC requests, log filters and block payloads
    Resources & endpoints
    Read-only preview
    You're browsing the public Firehose reference. Sign in to open a live stream with your team's API key.

    Cursors & live streaming

    STEP_NEW
    Process the incoming block. It may still be undone by a reorganization.
    STEP_UNDO
    Roll back the previously processed block identified by this response.
    STEP_FINAL
    The block is final according to the chain's finality rules; returned in final_blocks_only mode.

    Persist the response cursor after processing the block and its step. Reconnect with that cursor and the same filters. Handle stream errors and reconnect with backoff; do not parse or construct cursors yourself.

    The Node.js example uses a 16 MiB HTTP/2 receive window and a separate 64 MiB message limit. The larger window resolved a client backlog in the Robinhood comparison; size these settings for your workload. Filtering reduces payload and decoding work without changing when the chain executes a transaction.

    Try It previews stop after 15 seconds, 50 responses or a data limit. Preview timing includes the App proxy and connection setup. For direct delivery measurements, use a native client. Free and Pro share delivery infrastructure and streaming bandwidth limits; usage allowances differ.