Flashbots

Flashbots Auction Relay (JSON-RPC)

JSON-RPC endpoint for submitting bundles and private transactions to the Flashbots block builder. Supports eth_sendBundle, eth_callBundle, eth_cancelBundle, eth_sendPrivateTransaction, eth_cancelPrivateTransaction, mev_sendBundle, mev_simBundle, and fee refund methods. Requests are authenticated with an X-Flashbots-Signature header (EIP-191).

GitHub

Documentation

📖
Documentation
https://docs.flashbots.net/flashbots-auction/advanced/rpc-endpoint
📖
Authentication
https://docs.flashbots.net/flashbots-auction/advanced/rpc-endpoint#authentication

Other Resources

🔗
Repository
https://github.com/flashbots/rpc-endpoint
🔗
APIsJSON
https://raw.githubusercontent.com/api-evangelist/flashbots/refs/heads/main/apis.yml

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API entry from apis.yml

apis.yml Raw ↑ 
aid: flashbots:auction-relay
name: Flashbots Auction Relay (JSON-RPC)
description: JSON-RPC endpoint for submitting bundles and private transactions to the Flashbots block
  builder. Supports eth_sendBundle, eth_callBundle, eth_cancelBundle, eth_sendPrivateTransaction, eth_cancelPrivateTransaction,
  mev_sendBundle, mev_simBundle, and fee refund methods. Requests are authenticated with an X-Flashbots-Signature
  header (EIP-191).
humanURL: https://docs.flashbots.net/flashbots-auction/advanced/rpc-endpoint
baseURL: https://relay.flashbots.net
tags:
- JSON-RPC
- Bundles
- Private Transactions
- Auction
- Ethereum
properties:
- type: Documentation
  url: https://docs.flashbots.net/flashbots-auction/advanced/rpc-endpoint
- type: Authentication
  url: https://docs.flashbots.net/flashbots-auction/advanced/rpc-endpoint#authentication
- type: Repository
  url: https://github.com/flashbots/rpc-endpoint