Docs for cert and issuerId properties

Some of the blockcert samples, and their associated issuerId URL, have object properties for which I can’t find any docs. I’m hoping someone could quickly explain them, or point me at docs (I’m happy to contribute towards docs if that helps).

For the certs, these two properties (as taken from: https://blockcerts.learningmachine.com/certificate/ab56912734bb5784bced00b7e0e82ac9)
:

"nonce": "814ce340-12f3-414b-af91-a0f9489e5dbc",
"universalIdentifier": "ab569127-34bb-5784-bced-00b7e0e82ac9",

and for the issuerId (as taken from https://blockcerts.learningmachine.com/issuer/5a4fe9931f607f0f3452a65e.json
:

"introductionAuthenticationMethod": "none",
"introductionSuccessURL": "https://blockcerts.learningmachine.com/api/organization/accept-success",
"introductionErrorURL": "https://blockcerts.learningmachine.com/api/organization/accept-failed",
"analyticsURL": "https://blockcerts.learningmachine.com/api/event/certificate",
"issuingEstimateAuth": "unsigned",
"issuingEstimateUrl": "https://blockcerts.learningmachine.com/api/estimate"

Thank you,

James

any explanation on how to use those fields ?

"introductionAuthenticationMethod": "none",
"introductionSuccessURL": "https://blockcerts.learningmachine.com/api/organization/accept-success",
"introductionErrorURL": "https://blockcerts.learningmachine.com/api/organization/accept-failed",
"analyticsURL": "https://blockcerts.learningmachine.com/api/event/certificate",
"issuingEstimateAuth": "unsigned",
"issuingEstimateUrl": "https://blockcerts.learningmachine.com/api/estimate"