All money in and out is a decimal string (
"25.00", not 25 and not 25000000).
See Money & precision.1. Get your key
Create an API key in the Murmo app. At app.murmo.xyz, go to Account → Settings → REST and click Generate key (on mobile: Settings → API keys → Generate key). Give it a label, optionally set an expiry, and copy the key — it’s shown once. Production keys start withmurmo_live_.
Treat it like a password — it can move funds on your behalf. Store it in an environment variable:
2. Confirm who you are
200 with your userId means the key works. A 401 means the header is missing or the key is
invalid — check it starts with murmo_ and is sent as Authorization: Bearer ....
3. Check your wallet
Response
4. Fund it
Funding is one step: send USDC on Solana to thedeposit.walletAddress above. USDC is the only
token you ever hold; once the transfer lands, cashBalanceUsd reflects it. (Withdrawals aren’t
available over the API; they require the app.)
5. Your first trade
Trades on Murmo live as proposals inside groups (your trading circles). Spot, predictions, and perps all work the same way. Opening a proposal is leader/admin only, so first create a group to trade in (you become its admin):groupId. Creating it places the opening buy in a single call:
{ data: { proposal, trade } } — keep proposal.id to buy more, sell, or close later.
Response
6. Buy into an existing proposal
To add to a proposal — your own or one a groupmate opened — call/buy with amountUsd (USDC to
spend), or max: true to spend your full USDC balance:
buy, sell, or close the proposal, and others in the group can follow it.
See the Spot trading guide and Groups & proposals.
Predictions
Prediction markets work as soon as you’re funded — no extra setup. The only gate is regional: the two calls that open or add to a position —POST /api/v1/predictions/proposals and
POST /api/v1/predictions/proposals/{id}/predict — return 403 with code: "GEO_RESTRICTED" in
restricted regions. Reads, selling, and claiming are never gated.
See Eligibility & geo restrictions for the details, and the
Prediction agent flow for an end-to-end example.
Where to next
Money & precision
The one rule that prevents the most bugs.
Authentication
Keys, the Bearer header, and rate limits.
Prediction markets
Predict YES/NO on real-world events.
Perpetuals
Leverage, brackets, and live PnL.