> ## Documentation Index > Fetch the complete documentation index at: https://docs.byzantine.fi/llms.txt > Use this file to discover all available pages before exploring further. # Step 2 Send invitations (passkey) > Send an invitation to users to join a Byzantine account. If the users did not yet do a KYC on Byzantine, an email will ask them to do so. ## OpenAPI ````yaml /api-reference/openapi-integrator.json post /v1/submit/invite-users openapi: 3.0.3 info: title: Byzantine Integrator API description: Byzantine REST API for integrators. license: name: '' version: 0.2.0 servers: - url: https://sandbox.api.byzantine.fi description: Sandbox security: [] tags: - name: API health description: Check API status. - name: Customer management description: Endpoints to create, update, and retrieve customer information. - name: Account management description: Endpoints to manage accounts, bank accounts, invitations, and user roles. - name: Products description: Endpoints to get data about products and vaults. - name: Transactions description: Endpoints to create and manage transactions. - name: OTP authentication description: Endpoints to initialize and manage user authentication with OTP. - name: Webhooks description: Integrator-managed outbound webhook subscriptions and delivery history. paths: /v1/submit/invite-users: post: tags: - Account management summary: Step 2 Send invitations (passkey) description: >- Send an invitation to users to join a Byzantine account. If the users did not yet do a KYC on Byzantine, an email will ask them to do so. operationId: invite_users parameters: - name: X-Pubkey in: header description: >- Integrator's ECDSA public key (P-256 curve, compressed SEC1 format). Example: 0x038fedef7c12f93bbf342ad8943b7a825a3b41f61c9dc118b2c718efebabbf62fd required: true schema: type: string - name: X-Timestamp in: header description: >- Unix timestamp in seconds (UTC). Must be within tolerance window (1 minute) to prevent replay attacks. Example: 1760375826 required: true schema: type: string - name: X-Signature in: header description: >- ECDSA signature (DER-encoded, hex with 0x prefix). Signs the message: {timestamp}{METHOD}{path_and_query}{json_body}. Example: 0x3045022100... required: true schema: type: string requestBody: description: Body to invite new users to an existing account content: application/json: schema: $ref: '#/components/schemas/InviteUsersRequestBodyPasskey' required: true responses: '201': description: Users invited successfully content: application/json: schema: $ref: '#/components/schemas/InviteUsersResponse' '400': description: Invalid request payload '401': description: Unauthorized - Account does not belong to integrator '500': description: Internal server error security: - integrator_auth: [] components: schemas: InviteUsersRequestBodyPasskey: type: object required: - signedBody - invitedBy - webAuthnStamp properties: signedBody: $ref: '#/components/schemas/CreateUsersRequest' invitedBy: $ref: '#/components/schemas/Uuid' webAuthnStamp: type: string description: >- Cryptographically passkey signed (stamped). For more info, see [authentication methods](https://docs.byzantine.fi/api-reference/authentication-methods). InviteUsersResponse: type: object description: >- Response body when new users are successfully invited to a Byzantine account required: - accountId - newUsers - invitedBy - invitedAt properties: accountId: $ref: '#/components/schemas/Uuid' newUsers: type: array items: $ref: '#/components/schemas/InvitedUser' invitedBy: $ref: '#/components/schemas/Uuid' invitedAt: type: string format: date-time description: The timestamp when the users were invited. CreateUsersRequest: type: object description: >- The object that needs to be signed by the end user to invite a new user to a Byzantine account. required: - type - timestampMs - organizationId - parameters properties: type: type: string description: Defaults to `ACTIVITY_TYPE_CREATE_USERS_V3` example: ACTIVITY_TYPE_CREATE_USERS_V3 timestampMs: type: string description: UNIX timestamp of the creation of the request. organizationId: type: string description: The account ID adding the new user. example: d107c1e1-766a-4091-802c-de61a3973e91 parameters: $ref: '#/components/schemas/CreateUsersParams' Uuid: type: string format: uuid description: A UUID string example: 550e8400-e29b-41d4-a716-446655440000 InvitedUser: type: object description: The details of the new users invited. required: - userId - firstName - lastName - userEmail properties: userId: $ref: '#/components/schemas/Uuid' firstName: type: string description: The first name of the new user. example: John lastName: type: string description: The last name of the new user. example: Doe userEmail: type: string description: The email of the new user. example: john.doe@example.com CreateUsersParams: type: object description: The list of new users to be added. required: - users properties: users: type: array items: $ref: '#/components/schemas/CreateUserParam' CreateUserParam: type: object description: >- The parameters object containing the specific informations about the new user to be added. required: - userName - userEmail - apiKeys - authenticators - oauthProviders - userTags properties: userName: type: string description: The name of the new user. example: John Doe userEmail: type: string description: The email of the new user. example: john.doe@example.com apiKeys: type: array items: $ref: '#/components/schemas/ApiKeyParam' authenticators: type: array items: $ref: '#/components/schemas/AuthenticatorParam' oauthProviders: type: array items: $ref: '#/components/schemas/OAuthProviderParam' userTags: type: array items: type: string description: A list of tag IDs to add to the user. ApiKeyParam: type: object description: >- API key object. If set, temporary authentication method until the user adds a passkey. required: - apiKeyName - publicKey - curveType properties: apiKeyName: type: string description: Human-readable name for the API key. example: Byzantine API Key publicKey: type: string description: The public key of the API key. example: c51b102585622c59715784828c579278d5360159cd214fc976f5ce537c41872231 curveType: type: string description: The curve type of encryption algorithm. example: API_KEY_CURVE_P256 expirationSeconds: type: string description: >- Optional window (in seconds) indicating how long the API Key should last. example: '3600' nullable: true AuthenticatorParam: type: object description: Passkey authenticator object. required: - authenticatorName - challenge - attestation properties: authenticatorName: type: string description: Human-readable name for an Authenticator. challenge: type: string description: Challenge presented for authentication purposes. attestation: $ref: '#/components/schemas/Attestation' OAuthProviderParam: type: object required: - providerName - oidcToken properties: providerName: type: string oidcToken: type: string Attestation: type: object required: - credentialId - clientDataJson - attestationObject - transports properties: credentialId: type: string description: The cbor encoded then base64 url encoded id of the credential. clientDataJson: type: string description: >- A base64 url encoded payload containing metadata about the signing context and the challenge. attestationObject: type: string description: >- A base64 url encoded payload containing authenticator data and any attestation the webauthn provider chooses. transports: type: array items: $ref: '#/components/schemas/Transports' Transports: type: string enum: - AUTHENTICATOR_TRANSPORT_BLE - AUTHENTICATOR_TRANSPORT_INTERNAL - AUTHENTICATOR_TRANSPORT_NFC - AUTHENTICATOR_TRANSPORT_USB - AUTHENTICATOR_TRANSPORT_HYBRID - Unknown securitySchemes: integrator_auth: type: apiKey in: header name: X-Pubkey, X-Timestamp, X-Signature ````