# Docs

- Build with AI
  - [Build with AI](/docs/mcp): Connect FaceSign to your AI coding tool and ship a working verification integration in minutes.
  - [Localization](/docs/guides/multilingual)
  - [Conversation Rules](/docs/guides/conversation-rules)
  - [Verification Patterns](/docs/guides/verification-patterns)
- Use Cases
  - [Wire Transfer Authorization](/docs/use-cases/wire-transfer): Add step-up verification before high-value wire transfers — the #1 enterprise use case for FaceSign.
  - [Account Recovery](/docs/use-cases/account-recovery): Let users recover locked accounts through face verification instead of passwords or security questions.
  - [Step-Up from Anomaly Detection](/docs/use-cases/anomaly-stepup): Trigger FaceSign verification when your fraud system detects suspicious activity.
  - [Payment Authentication](/docs/use-cases/payment-auth): Use FaceSign as a 3D Secure alternative for high-risk payment authorization.
- Guides
  - [Webhooks](/docs/guides/add-webhooks): Receive real-time notifications when session events occur.
  - [Session Customization](/docs/guides/customize-branding): Customize the FaceSign verification permissions page and UI controls for a branded user experience.
  - [Custom Pages](/docs/guides/custom-pages): Wrap the FaceSign session with your own landing and recap pages when you generate an app through the MCP server.
  - [Production Checklist](/docs/guides/production-checklist): Everything to verify before moving your FaceSign integration from sandbox to production.
- Security
  - [Security Architecture](/docs/security/architecture): Six parallel AI defense layers, HSM tokenization, encryption, and data flow.
  - [Biometric Data Handling](/docs/security/biometric-data): How FaceSign processes, stores, and deletes biometric data, and how long it is retained.
  - [Liveness and deepfake detection](/docs/security/deepfake-detection): Configure liveness and post-session analysis, interpret their results, and understand capture limitations.
  - [Coercion & Duress Detection](/docs/security/coercion-detection): FaceSign's crown jewel: detecting when a user is acting under duress during verification.
  - [Audit & Evidence](/docs/security/audit-evidence): What FaceSign retains for audit purposes, how to retrieve it, retention periods, and known gaps.
  - [Compliance & Regulatory](/docs/security/compliance): GDPR, CCPA, BIPA, SOC 2, ISO 27001, and PSD3 regulatory alignment for FaceSign deployments.
- Reference
  - [Concepts](/docs/reference/concepts): The mental model — sessions, flows, nodes, and reports. Read this once; build confidently.
  - [Authentication](/docs/reference/authentication): API keys, Bearer token format, client secrets, rate limits, and retry guidance.
  - [Node Reference](/docs/reference/node-reference): Complete reference for all FaceSign verification node types — parameters, outcomes, and configuration.
  - [Webhook Events](/docs/reference/webhook-events): All FaceSign webhook event types with payload schemas and delivery behavior.
  - [Error Handling](/docs/reference/errors): Learn how to handle errors when using the FaceSign API.
  - [Languages](/docs/reference/languages): Learn how to retrieve and use supported languages for FaceSign verification sessions.
  - [Avatars](/docs/reference/avatars): Learn how to retrieve and use AI avatars for conversational verification experiences.
  - [SDKs](/docs/reference/sdks): Official SDKs and client libraries for integrating FaceSign step-up verification into your applications.
  - [Known Behaviors](/docs/reference/known-behaviors): Intentional platform behaviors and edge cases to design around.
  - [Client Secrets](/docs/reference/client-secrets): Short-lived, session-scoped tokens for redirecting users to the hosted verification flow.
  - [Changelog](/docs/reference/changelog): Platform and documentation changes, newest first. Use this to plan integration maintenance windows.
- REST API Reference
  - [List sessions](/docs/api-reference/listSessions): Retrieve a paginated list of sessions with optional filtering
  - [Create a verification session](/docs/api-reference/createSession): Creates a session with an executable flow. Supply language IDs returned
by GET /langs, such as en, rather than display names such as English.
The deprecated modules field is rejected. See the flow examples and
validation behavior in the guides before opening the session.
  - [Retrieve a session](/docs/api-reference/getSession): Get details and status of a specific verification session
  - [Create a client secret](/docs/api-reference/createClientSecret): Replace the client secret only while a session is still created and has
never started. This preserves the existing session state. An inProgress
session returns session_in_progress; complete and incomplete sessions
return session_finished. Create a new session for a new verification.
  - [Get supported languages](/docs/api-reference/getLangs): Retrieve a list of all supported languages
  - [Get available avatars](/docs/api-reference/getAvatars): Retrieve a list of all available avatars