OnLink Partner API
Convert between Kenyan shillings and USDT from inside your own product. Start with the plain-language overview, or go straight to a signed first call.
OnLink is a business-to-business API for converting between Kenyan shillings (KES) and USDT, a US-dollar stablecoin that moves over the Tron network. You tell us which way you want to go and how much. We lock a rate, take in your funds, pay out the other currency to a destination you registered with us, and send you a signed message when it is done.
You do not need to know anything about blockchains or bank rails to follow these docs. The Overview explains the product in plain language, with no code. The technical sections begin at Get started.
Choose your path
I want to understand the product
What the API does, how a conversion works, what you can build with it, and a glossary of every term. Written for product, business and compliance readers.
I want to make my first call
Get sandbox credentials, sign a request and take a live quote, in curl, Node or Python. Then run a complete order end to end.
I am building with an AI agent
llms.txt, the whole corpus as one file, every page as Markdown and a read-only MCP server. Point your agent at the docs and let it read.
What you can build
Pay out Kenyan shillings from USDT
You send USDT; shillings land in a bank account you registered.
Take Kenyan shillings, deliver USDT
Your payer sends shillings to your collection account; USDT lands at an address you registered.
Know the moment an order finishes
We send a signed webhook when your funds are confirmed and when the order reaches its final state.
Control where value can go
Payout accounts and withdrawal addresses are registered ahead of time, so a credential can never invent a new destination.
Remittance operators, exchanges, treasury teams and platforms paying suppliers in Kenya combine these in different ways. See Use cases for how.
How a conversion works
Every order, in either direction, follows the same four steps:
- Lock a rate. You ask for a quote and we hold that rate for a short window.
- Create an order against the quote, with a reference of your own.
- Fund it. Send the USDT, or have your payer send the shillings.
- We settle and tell you. We confirm your funds, pay out the other side, and send you a webhook at each step.
Settlement is not immediate. The order is created first and completes later, the way a bank transfer does rather than a tap-to-pay. That one fact shapes how an integration is built, so it has its own page: How it works for the plain-language version and Asynchronous settlement for the version you build against.
Find your way around
Get started
Credentials, request signing, your first call, and how sandbox works.
Guides
Which flow you need, the four stages every order goes through, and a step-by-step guide for each direction.
Concepts
Settlement, money, quotes, idempotency, limits, and who does what.
Webhooks
The four events, delivery and retries, and how to verify a signature.
Rails
Kenyan shillings, USDT on Tron, and how the rate is quoted.
API reference
Every operation, generated from the running service, with a downloadable OpenAPI spec.
Errors
One error envelope, every code you can branch on, and what to retry.
Changelog
What changed, and what we count as a breaking change.
Environment
Every example in these docs uses the sandbox at
https://sandbox.onlink.africa. Sandbox is where you integrate and certify.
Production access is enabled per partner once your integration is ready, and
nothing in your code changes except the base URL and your credentials. Read
Sandbox for what it can and cannot do.
Getting help
Email info@onlink.africa with integration
questions, incidents and credential requests. It is a monitored inbox. Check
onlink.africa/status first if something looks
wrong, and quote the requestId from any error response when you write to us
— it is the one handle that finds your request in our logs. See
Status and support for what to include.