There are currently two major versions of the Overledger API. Version 2 and Version 3.

Version 2 endpoints can be identified by the presence of /v2 in the path:

api.overledger.dev/v2/preparation/transaction)

Version 3 (and future versions) can be identified by the presence of /api in the path:

api.overledger.dev/api/webhooks/smart-contract-events)

Starting with version 3, since the version number is no longer present in the API path, you will need to instead specify which version of the API you want to call via an "Api-Version" header parameter. The API-Version parameter will need to be set with the desired version value (e.g. 3.0.0).

curl --request POST \
     --url https://api.overledger.dev/api/webhooks/smart-contract-events \
     --header 'API-Version: 3.0.0' \
     --header 'accept: application/json' \
     --header 'content-type: application/json' \
     --data '
{
  "location": {
    "technology": "ethereum",
    "network": "ethereum sepolia testnet"
  },
  "callbackUrl": "http://www.example.com",
  "smartContractId": "0xpo98iuytgbnmjkoi87ytghjiu"
}
'