LINE Login v2.1
End-user authentication and authorization over OAuth 2.0 authorization code grant and OpenID Connect. Authorization runs at access.line.me; token, userinfo, revocation and JWKS endpoints are on api.line.me. ID tokens are ES256-signed JWTs with pairwise subject identifiers, PKCE is supported with S256 only, and JARM response modes (jwt, query.jwt, form_post.jwt) are accepted. Scopes are openid, profile and email. LINE publishes no OpenAPI for this surface — the machine-readable contract is the OIDC discovery document.