Lightning Labs this week released the alpha version of Wavelength, a toolkit that lets developers and AI agents add self-custodial Bitcoin payments to their applications without running nodes or managing channels. The non-custodial API embeds a wallet that keeps user keys on-device, supporting on-chain Bitcoin, Lightning payments via atomic swaps, and an Ark-like settlement layer for fast off-chain transfers.
No node, no channel management
Wavelength eliminates the operational overhead that has kept many developers from integrating Bitcoin payments directly. The toolkit embeds a self-custodial wallet that runs inside web and mobile apps via WebAssembly or compiled binaries, or as a standalone client. User-controlled keys stay on-device. For payments, it supports on-chain Bitcoin, Lightning via atomic swaps, and an Ark-like settlement layer that batches off-chain transfers for speed and low cost. Every off-chain payment uses a standard BOLT 11 invoice, ensuring interoperability with the existing Lightning Network. Lightning payments route through Loop for deep, reliable liquidity. A coordination service settles transfers between users but never takes unilateral control of funds — users can always perform a unilateral exit to on-chain Bitcoin via an explicit exit command. The Wavelength SDK is open source.
AI agents get their own payment rail
The same Wavelength API is exposed to AI agents as typed tool calls through the Model Context Protocol (MCP). Agents can hold balances and pay for API calls, data feeds, or other agent services in fractions of a cent. Wallet creation and unlocking are designed to remain outside the agent channel so seeds and passwords are not exposed to the model. Wavelength also integrates with L402, Lightning Labs’ protocol for machine-native authentication and per-request Lightning payments. Core commands cover the full lifecycle: create/unlock, balance, recv (for addresses or invoices), send, activity, and exit. Integration options include the embedded SDK, a gRPC/REST API, a browser WASM package, and an MCP server.
Signet and testnet now, mainnet by invitation
Wavelength is available immediately on Signet and testnet. Mainnet access is invitation-only. Bitcoin is supported at launch; stablecoin support is planned via Taproot Assets. Future work includes deeper mobile embedding and optional direct Lightning channel support using Lnd. During the closed alpha, Lightning transactions carry a minimal 1 basis point service fee plus standard network routing fees, with ordinary Bitcoin network fees applying for on-chain activity. Pricing may evolve as the toolkit moves toward a wider release. Lightning Labs described Wavelength as 'Bitcoin on Easy Mode for Agents and Humans.'
