Organization Domain - The domain of your Salesforce org instance that the application/client authenticates against and to which it sends API requests.
Client ID - The public value that indicates which application is requesting access.
Client Secret - The secret key associated with the Client ID, used to prove the application’s identity during OAuth authentication (must be kept confidential).
Agent ID - The unique identifier of the specific Agentforce agent (resource) you want to call, used to route requests to that exact agent/configuration.
How to Obtain Required Fields
Follow these instructions from official Salesforce docs to register a Salesforce App.
Follow the Obtain Credentials step to mint Consumer Key (Client ID) and Consumer Secret (Client Secret).
You can get the Organization Domain from the Setup menu in the top right corner of the Agentforce app. Search for My Domain. Copy the value shown in the Current My Domain URL field.