Status group¶

Execution lifecycle for a record is stored in the status group. It is used for monitoring, resume decisions, and UI summaries. Scientific result arrays live on frame, trajectory, or observables; time series of measurements live on metrics.

In the reference binding the contents are group attributes (one JSON object). status.state is required whenever the group exists.

status
 +-- state: string[]
 +-- (stage: string[])
 +-- (epoch)
 +-- (global_step)
 +-- (message: string[])
 +-- (started_at: string[])
 +-- (updated_at: string[])
 +-- (finished_at: string[])
 +-- (error)
 \-- ...

state

Lowercase lifecycle: pending, running, succeeded, failed, cancelled, skipped. Writers may preserve custom states.

stage

Current execution phase, independent of lifecycle state (e.g. train, eval, simulate).

epoch, global_step

Reserved counters: non-negative JSON integers. Extra counters go under status.progress, an object of named numbers.

message

Free text for a human.

started_at, updated_at, finished_at

RFC 3339 timestamps with an explicit offset (Z or ±hh:mm); a timestamp without one names no instant and is not valid here.

error

Present when state is failed: an object with at least message (string), and optionally type (string) and traceback (string).

Every key a producer adds beyond these is preserved.

A run-shaped record is meta plus status, optionally with metrics and method. frame is optional. See Run surface.