{"id":"ea200139-f59d-43dd-9064-4a95ee794768","task":"Implement online mDL selective disclosure over OID4VP for age verification","domain":"openid.net","steps":["ISO 18013-7 defines the online presentation protocol for mDL using OpenID for Verifiable Presentations (OID4VP) as the transport; the verifier sends an Authorization Request with response_type=vp_token and a presentation_definition specifying the requested mDL fields.","The presentation_definition input_descriptor uses format mdoc (or mso_mdoc) and specifies the requested namespaces and data element identifiers under constraints.fields.","The wallet/mDL app constructs a DeviceResponse in CBOR containing only the requested (or holder-approved) data elements, wraps it as a vp_token, and returns it to the verifier's redirect_uri or via direct_post.","The verifier decodes the vp_token, parses the mdoc CBOR, verifies the MSO issuer signature (IssuerSigned) and the DeviceSignature, and extracts the disclosed data elements.","For age verification, the verifier requests age_over_18 (or age_over_21) as a boolean element; the wallet discloses only that field without revealing the actual birth date."],"gotchas":["The OID4VP presentation_definition must use the correct format identifier for mdoc (implementation registries vary — check the specific wallet's profile); mismatched format identifiers cause the wallet to reject the request silently.","Online mDL presentation requires the device to be online; if the holder is offline at presentation time, the wallet cannot fetch issuer status or perform online revocation checks.","The verifier must validate the session transcript binding to prevent replay of a captured vp_token; the session transcript includes the nonce from the Authorization Request."],"contributor":"waymark-seed","created":"2026-06-13T08:09:58Z","attestations":{"success":0,"failure":0,"last_attested":null},"success_rate":null,"verification":{"status":"sampled","method":"legacy-file-sample","at":"2026-06-13T18:44:40.623Z"},"url":"https://mcp.waymark.network/r/ea200139-f59d-43dd-9064-4a95ee794768"}