Update keysend docs

diff --git a/lightning/src/ln/channelmanager.rs b/lightning/src/ln/channelmanager.rs
index 24c0c688cf0843274a61954433098d31324810a5..67ca27fb8ad2d64aedf3acca05c39299ea0503a5 100644 (file)
--- a/lightning/src/ln/channelmanager.rs
+++ b/lightning/src/ln/channelmanager.rs
@@ -1912,9 +1912,13 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        /// would be able to guess -- otherwise, an intermediate node may claim the payment and it will
        /// never reach the recipient.
        ///
+       /// See [`send_payment`] documentation for more details on the return value of this function.
+       ///
        /// Similar to regular payments, you MUST NOT reuse a `payment_preimage` value. See
        /// [`send_payment`] for more information about the risks of duplicate preimage usage.
        ///
+       /// Note that `route` must have exactly one path.
+       ///
        /// [`send_payment`]: Self::send_payment
        pub fn send_spontaneous_payment(&self, route: &Route, payment_preimage: Option<PaymentPreimage>) -> Result<PaymentHash, PaymentSendFailure> {
                let preimage = match payment_preimage {