MEV-Boost Relay API specification v1.

The Flashbots mev-boost-relay is open source:

Links to API specs:

See also:

Error responses

All API errors follow the following schema (where code is the same as the HTTP request response status code):

  "code": 400,
  "message": "description about the error"

Block Builder API

The block builder API allows block submissions to the MEV-Boost Relays.

The block submission rate limit is 2 submissions / second / IP.