SubgraphDiscoverySnapshot

Wall-clock timestamp when the task tool terminated (null if running).

Name of the graph node that produced this subgraph invocation, parsed from the last namespace segment. LangGraph assigns every node invocation a checkpoint namespace shaped like <node_name>:<uuid>; this is the <node_name> half, letting callers key lookups on names they recognise from addNode(name, …) without parsing the namespace themselves.

Wall-clock timestamp when the task tool started.