The consensus client submits a received execution payload through
engine_newPayload. The execution client returns PayloadStatusV1.
Status values
VALID means the payload and its ancestors are valid. INVALID means the
payload is invalid. SYNCING means the client lacks data needed to decide.
ACCEPTED means it accepted the payload for later processing.
latestValidHash identifies the last valid execution ancestor when known.
validationError may explain an invalid result but is not a stable machine
interface.
The active engine_newPayloadV* method returns INVALID, not
INVALID_BLOCK_HASH, when the supplied execution block hash does not match the
payload.
Wire surface
The valid method is engine_newPayloadV4.
Consensus response
The consensus client can import a VALID payload normally. It keeps a
SYNCING or ACCEPTED block optimistic and must not finalize it before
validation. Payload validity is idempotent: a payload that is VALID or
INVALID must not switch to the other state on a later validation pass. For
INVALID, it removes the invalid branch from consideration and uses
latestValidHash to find the valid boundary.
Failure handling
Invalid parameters, unsupported fork, and transport failure are not payload validity results. The consensus client retries a timeout when needed. It treats conflicting execution-client answers as a local safety fault and does not guess which branch is valid.
Design rationale
The status model keeps invalid payloads separate from payloads that the execution client cannot validate yet.