what's Wallet Development Kit (WDK) by Tether?

The Wallet Development Kit (WDK) by Tether is an open-source toolkit that empowers developers, machines, AI agents, and IoT devices to build, deploy, and operate secure, multi-chain, self-custodial wallets. It supports Bitcoin, Tether tokens like USDT, EVM-compatible chains, and extensible modules for additional protocols, offering unified APIs for wallet creation, transactions, swaps, bridges, lending, balance queries, and blockchain indexing. Designed for flexibility across Node.js, React Native, bare runtimes, and future embedded environments, WDK features a modular SDK with TypeScript typing, CLI for instant setups, reusable UI components, and production templates. For AI agents, it provides "Agent Skills" enabling autonomous operations with built-in safeguards like human confirmation for writes, fee estimation, prompt-injection protection, and local key management, ensuring cypherpunk principles of "not your keys, not your coins" in agentic economies.[[1]](https://docs.wdk.tether.io/overview/about)[[2]](https://wdk.tether.io/)[[3]](https://docs.wdk.tether.io/)[[4]](https://messari.io/project/wdk-tether/profile)

WDK by Tether is an open-source toolkit for building secure, multi-chain, self-custodial wallets.