tooltip
Tooltip (mouse hover text) attached to the node, edge, cluster, or graph
type: escString, default: ""
If tooltip is unset, Graphviz will use the object's label if defined.
Note
that if the label is a record specification or an HTML-like label, the
resulting tooltip may be unhelpful. In this case, if tooltips will be
generated, the user should set a tooltip attribute explicitly.
      
        Tooltips
      
    
  
  digraph {
  label="Graph Label"
  tooltip="Graph Tooltip"
  subgraph cluster_a {
    label="Cluster Label"
    tooltip="Cluster Tooltip"
    Node1 [tooltip="Node1 Tooltip"]
    Node1 -> Node2 [label="Edge" tooltip="Edge Tooltip"]
  }
}See also:
Valid on:- Nodes
 - Edges
 - Clusters
 - Graphs