UML use-case (with stick-figure actors)

{
  "nodes": [
    { "id":"u1","type":"actor","label":"Customer","x":40,"y":120 },
    { "id":"u2","type":"actor","label":"Admin","x":40,"y":360 },
    { "id":"uc1","type":"ellipse","label":"Browse catalog","x":260,"y":40,"fill":"#dbeafe","stroke":"#2563eb" },
    { "id":"uc2","type":"ellipse","label":"Add to cart","x":260,"y":140,"fill":"#dbeafe","stroke":"#2563eb" },
    { "id":"uc3","type":"ellipse","label":"Checkout","x":260,"y":240,"fill":"#dbeafe","stroke":"#2563eb" },
    { "id":"uc4","type":"ellipse","label":"Track order","x":260,"y":340,"fill":"#dbeafe","stroke":"#2563eb" },
    { "id":"uc5","type":"ellipse","label":"Manage inventory","x":260,"y":440,"fill":"#ede9fe","stroke":"#6d28d9" },
    { "id":"sys","type":"rect","label":"<<system>>\nShop","x":520,"y":240,"fill":"#fef3c7","stroke":"#a16207" }
  ],
  "edges": [
    { "id":"e1","source":"u1","target":"uc1" },
    { "id":"e2","source":"u1","target":"uc2" },
    { "id":"e3","source":"u1","target":"uc3" },
    { "id":"e4","source":"u1","target":"uc4" },
    { "id":"e5","source":"u2","target":"uc5" },
    { "id":"e6","source":"uc1","target":"sys" },
    { "id":"e7","source":"uc2","target":"sys" },
    { "id":"e8","source":"uc3","target":"sys" },
    { "id":"e9","source":"uc4","target":"sys" },
    { "id":"e10","source":"uc5","target":"sys" }
  ]
}