Build against the sandbox first. Every example in these docs works against
https://api.sand.etherfuse.com with no real money or personal data. Start with the Quickstart.Get started
Quickstart
Register payment accounts, quote, create an order and fund it in sandbox.
Initial setup
Create a sandbox account, generate API keys, and learn the base URLs.
Onboard a customer
Run KYC with a single hosted launch (
/idv).API Reference
Browse all endpoints with live “Try it” requests and code samples.
What you can build
Onramp
Customer pays fiat from a bank account, receives tokens in a wallet.
Offramp
Customer sends tokens from a wallet, receives fiat in a bank account.
Swap
Customer exchanges one token for another on the same chain.
Cross-chain transfer
Customer sends a token from a wallet on one supported chain to a wallet on another.
Core concepts & reference
How it works
Payment accounts, rails, quotes, orders and their statuses.
Authentication
API-key auth, sandbox vs. production keys, and the one header gotcha.
Errors
Every problem type the API returns, with causes and fixes.
Pagination
How to page through payment accounts, orders and subscriptions.
Idempotency
Retry order creation with the same
quoteId and get one order.Webhooks
Signed event delivery for orders, payment accounts and KYC.
SDKs
TypeScript and Rust libraries for the on-chain Stablebond side.
Build with AI & tools
MCP Server
Connect Claude, ChatGPT, or any MCP client and drive the Etherfuse API in natural language.
llms.txt
A machine-readable index of these docs for LLMs and AI assistants.
OpenAPI spec
Download
openapi-v2.json to import into Postman, Insomnia, or generate a client.