curl --request POST \
  --url https://api.iotools.cloud/v1/tool/pdf-signature-checker \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "file": "data:application/pdf;base64,JVBERi0xLjQKSGVsbG8sIHRoaXMgaXMgbm90IGEgc2lnbmVkIFBERi4="
}
'

{
  "tool": "pdf-signature-checker",
  "tool_version": "1.0.1",
  "outputs": {
    "summary": [],
    "certificates": [],
    "warnings": []
  },
  "credits_used": 3,
  "credits_remaining": null
}