Tools · Bridges & conversion
Boltz
Non-custodial atomic swaps between on-chain Bitcoin, Lightning, and Liquid — the submarine-swap bridge, exposed as an API.
What it is
Boltz is a non-custodial bridge that performs atomic (submarine) swaps between on-chain Bitcoin, Lightning, and Liquid, exposed via a RESTful API. Because the swaps are atomic, neither side can take the funds and run — it’s the trust-minimized way to move value across those rails without a custodian. For agent treasuries, Boltz is a building block for rebalancing and converting between layers at the boundary.
A bridge tool — it crosses between rails. This card is the infrastructure view of Boltz; its venue role (Lightning↔stablecoin conversion) has a separate exchange card. See The Marketplace for where conversion mechanics fit relative to the pure substrate.
When to use it
- Moving value between on-chain BTC, Lightning, and Liquid without a custodian.
- Acquiring inbound Lightning liquidity or sweeping to on-chain via atomic swaps.
- Programmatic conversion at the edge of an agent treasury.
Dependencies
Non-custodial wallets on the rails you’re swapping between (on-chain Bitcoin, Lightning, and/or Liquid) and a client-side integration of the API; swaps pay network fees plus a provider-set swap fee and need correct refund/timeout handling. No account, no KYC.
Quick start
Integrate against the API at api.docs.boltz.exchange; the service is powered by boltz-backend (github.com/BoltzExchange/boltz-backend), which you can also self-host. Follow the docs’ common-mistakes guide before going live.
Gotchas
- Non-custodial only if integrated correctly — Boltz explicitly warns integrators to keep API clients client-side and never run swaps or store refund data on users’ behalf, or the non-custodial guarantee breaks.
- Submarine swaps require correct refund/timeout handling; abandoned or failed swaps need user-controlled refund flows.
- Swap liquidity and limits are provider-set.
For agents — connect
Reach this programmatically — facts, not endorsements; verify before you depend on them.
- Prerequisite
- A funded wallet (custodial or self-custodial)
wallet - Automatability
api-no-account- Pay with
- lightning, onchain, liquid
- Auth
- none
- API base
https://api.boltz.exchange/v2- First call
- Create a swap against the v2 REST API — no account; atomic HTLC settlement keeps custody with the agent throughout (docs: api.docs.boltz.exchange).
In the marketplace directory: call get_service with slug boltz at /mcp · entry as data · this card as markdown.