# Codex conversation state 0.5.0
`ConversationState` owns the process-local Codex job, call-wave, submitted-frontier, and exact-once steer lifecycle. K1 Chat State owns transcript transactions, canonical `cN` allocation and recovery, FIFO arrivals, retries, and generic open boxes.
Codec values are validated before a stage reaches State. A malformed or non-call stage appends nothing and consumes no call ID. Successful stages preserve provider order and structured arguments. Provider-native IDs are never adopted.
A new native turn receives the unsubmitted transcript suffix. A prepared steer contains one finite FIFO snapshot and advances the submitted frontier only after commit. Cold recovery has no live native conversation and therefore reprojects the complete current transcript. Terminal completion accepts zero items or one text item only.
Failures before an accepted call wave may restart; failures after a call wave are terminal for that attempt. There is no legacy reader, nonce/sequence allocation, compatibility shim, or migration.