Ezrah DIDComm Protocol: OpenID4VC Protocols

Ezrah supports the DIDComm implementation of two major OpenID for Verifiable Credential Protocols:

openid4vcp: Requesting Verifiable Credentials
openid4vcp-presentation: Presenting Verifiable Credentials

This document outlines how to initiate and interact with these flows using Ezrah’s DIDComm protocol payload structure.

Protocol Types

`openid4vcp`

Used by an issuer (e.g., organization) to initiate a credential issuance process.

Example Payload


{
  type: "https://docs.ezrah.co/docs/didcomm-protocols/openid4vcp",
  id: verificationModel.id,
  from: organization.identifier?.did,
  body: {
    goal_code: `Login with ${organization.name}`,
    goal: verificationModel.purpose,
    verification_model: verificationModel.id,
    source: organization.name,
  },
  attachments: [
    {
      media_type: "application/json",
      data: {
        json: {
          presentation: "string"
        }
      }
    }
  ],
}

Fields

Field	Description
`type`	Protocol URI for openid4vcp
`id`	Unique identifier for the verification request, typically the `verificationModel.id`
`from`	DID of the requesting organization
`body.goal_code`	Displayed message, e.g. `Login with Acme Inc.`
`body.goal`	Purpose of the verification (e.g., login, KYC, registration)
`body.verification_model`	Reference to the verification model
`body.source`	Human-readable name of the organization
`attachments`	Contains the presentation definition required for issuance

`openid4vcp-presentation`

Used by a holder to present credentials in response to a request.

Expected Behavior

Upon receiving a openid4vcp request:

A wallet or agent will interpret the presentation definition and construct a Verifiable Presentation.
The holder responds with a openid4vcp-presentation message.

Example Payload (Conceptual)


{
  type: "https://docs.ezrah.co/docs/didcomm-protocols/openid4vcp-presentation",
  id: "unique-uuid-id",
  from: holderDid,
  to: verifierDid,
  body: {
 
  },
  attachments: [
    {
      format: "application/vc+ld+json",
      data: {
        base64: base64urlEncode(presentation)
      }
    }
  ]
}

Compatibility

Compliant with DIDComm v2
Based on OpenID for Verifiable Credential Issuance (OID4VCI)
Presentation Exchange 2.0 compliant

Use Cases

Decentralized Login
Reusable KYC
Verifiable Proof of Membership
Onboarding Automation
Trustless Access Control
Credential Authentication