Properties
number
required
Pass this as
targetNodeId to [REVERT_FORK_FROM_STEP_METHOD] to
fork a new session containing step N and everything before it.For a prompt step this is the last node produced by the turn (the
final assistant or tool message before the next user message, or the
chain tail). For a question step it is the question’s tool-result
node — the fork includes the old answer.string & object | RevertStepKind
required
Type:
RevertStepKindnull | number
Node ID of the assistant message containing the question tool call.
After executing a revert to this step, pass it as
questionNodeId to
[REVERT_RESUME_METHOD] to have the agent re-ask the question.
Present iff kind is [RevertStepKind::QuestionAnswer].null | number
Pass this as
targetNodeId to [REVERT_PREVIEW_METHOD] or
[REVERT_EXECUTE_METHOD] to undo step N and everything after it.For a prompt step this is the node just before the user message —
reverting to it rewinds the conversation to the state right before
the user sent their message. For a question step it is the node just
before the assistant message containing the question — reverting
discards the question, its answer, and everything after; the question
is then re-asked via [REVERT_RESUME_METHOD]. None when the
anchoring node has no predecessor (which should not happen in
practice because of the system-prefix node, but is represented as an
Option to avoid clients crashing on malformed chains).null | string
Stable anchor message identity. When present, pass this as
stepId
to preview/execute instead of retaining a chain-specific node ID.number
required
1-based index of this step in the session (matches the REPL’s
/steps).
Prompt and question steps share one interleaved numbering.string
required
Short human-readable summary of the user message or question text.
null | string
The question’s tool call ID — the stable identity for matching a
rendered Q&A to this step. Present iff
kind is
[RevertStepKind::QuestionAnswer].null | string
Stable UUID for the user message that starts this step.
Present iff
kind is [RevertStepKind::Prompt].