Available parameters and response documentation is available here

GET /lookup/chr22-29091857-G-?format=api
HTTP 200 OK
Allow: GET, HEAD, OPTIONS
Content-Type: application/json ;utf-8
ETag: "79e834656fea4a1f239b695584c05b0510bdd1ab187fdcfd531b82561b943f78"
Vary: Accept

{
  "chromosome": "chr22",
  "alt": "",
  "ref": "G",
  "pos": 29091857,
  "variant_id": "10190220290918579001",
  "variant_type": "Deletion",
  "cytobands": "22q12.1",
  "publications": {
    "publications": [],
    "genes": []
  },
  "publication_counts": [
    {
      "type": "variant",
      "id": "10190220290918579001",
      "count": 119
    }
  ]
}