A submission request is not control of the block
Transaction order is determined by chain rules and the block-production path. A sender can choose a transaction, bundle format, route, and supported conditions; that does not grant control over the final block or guarantee a preferred position.
EVM private bundles, Solana block-engine bundles, and ordinary public transactions are different submission paths. Their semantics and failure modes are provider- and chain-specific.
Compare the execution paths
EVM bundles
Flashbots bundles contain ordered transactions and can target inclusion conditions. Revert behavior depends on the submitted bundle options and the builder interface.
Solana bundles
Jito documents ordered, atomic bundle processing in its block-engine path. Its documentation also describes uncled-block cases where rebroadcast transactions may no longer receive bundle atomicity protections.
Ordinary transactions
A public or private transaction route changes who may see data and how it is forwarded. Read the endpoint rules; a private route is not a universal ordering or inclusion guarantee.
Questions to resolve before submission
What receives the request?
Identify the RPC, relay, or block engine, its current API, required authentication, data visibility, and retention terms.
What does acceptance mean?
Separate an API acknowledgement or bundle identifier from simulation success, block inclusion, and a confirmed transaction receipt.
What can revert?
Check the exact simulation state, target block, allowed-revert rules, and fee behavior in the selected provider documentation.
What if the route fails?
Document timeouts, rejection, fallback paths, duplicate submission risks, and state checks that protect against partial or rebroadcast execution.
Limits and failure cases
Simulation describes a request against a specified state and context; it is not a forecast of later state or inclusion. Flashbots notes that bundles target blocks and may not be included. Jito documents that transactions rebroadcast after an uncled block can enter normal processing without bundle atomicity protections. Design and test safeguards for the actual route you use.
Primary technical references
FRB Agent workflows
FRB Agent supports simulation-first review and private bundle workflows. Available paths depend on the selected chain and configured provider. Review the product documentation and risk disclosure; neither simulation nor private submission guarantees inclusion or a financial outcome.
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