# secondfactor.ai

> One API for two-factor authentication over SMS, WhatsApp, Viber, RCS and SNA.
> We generate, deliver and check the code, so you never store one. Twilio
> Verify v2 paths, authenticated with an X-API-Key header.

Coding agents: download the full reference with a plain HTTP client (for example
`curl -s https://api.secondfactor.ai/llms-full.txt`) and read all of it. A summarising web-fetch tool
drops the exact status codes and limits an integration depends on.

## Docs
- [Full integration reference](https://api.secondfactor.ai/llms-full.txt): endpoints, request and response bodies, every error code, rate limits, webhooks, and a step-by-step guide for building the integration.

## Dashboard
- [Settings](https://app.secondfactor.ai/dashboard/settings): the Service SID (starts with VA) and the DLR webhook.
- [API keys](https://app.secondfactor.ai/dashboard/keys): create an API key (starts with sf_); it is shown once.