Custody - Symbiosis

Custody holds user funds. Deposits arrive on per-user derived addresses and are credited after confirmation; balances are tracked per (venue, asset), with USDC held separately. Withdrawals are queued and settled asynchronously.

Endpoints

Endpoint	Purpose
`POST /custody/create-deposit-address`	Issue a deposit address on a chain
`GET /custody/get-deposit-addresses`	List the user’s deposit addresses
`GET /custody/get-balance`	Balance for a single `(venue, asset)`
`GET /custody/get-balances`	All balances, paginated
`GET /custody/get-usdc-balance`	USDC balance
`POST /custody/withdraw`	Queue a withdrawal to an external address
`GET /custody/get-withdrawals`	Withdrawal history with statuses and tx hashes
`GET /custody/get-ledger`	The journal of every credit and debit

Withdrawals require the withdraw scope. Sessions carry it; an API key only does if it was minted with it. A request without the scope returns 403.

Amounts are U256: hex strings in responses, and decimal strings, hex strings, or numbers in requests.