- /// If you fail to call either [`ChannelManager::claim_funds`], [`ChannelManager::fail_htlc_backwards`],
- /// or [`ChannelManager::fail_htlc_backwards_with_reason`] within the HTLC's timeout, the HTLC will be
- /// automatically failed.
+ ///
+ /// If [`Event::PaymentClaimable::onion_fields`] is `Some`, and includes custom TLVs with even type
+ /// numbers, you should use [`ChannelManager::fail_htlc_backwards_with_reason`] with
+ /// [`FailureCode::InvalidOnionPayload`] if you fail to understand and handle the contents, or
+ /// [`ChannelManager::claim_funds_with_known_custom_tlvs`] upon successful handling.
+ /// If you don't intend to check for custom TLVs, you can simply use
+ /// [`ChannelManager::claim_funds`], which will automatically fail back even custom TLVs.
+ ///
+ /// If you fail to call [`ChannelManager::claim_funds`],
+ /// [`ChannelManager::claim_funds_with_known_custom_tlvs`],
+ /// [`ChannelManager::fail_htlc_backwards`], or
+ /// [`ChannelManager::fail_htlc_backwards_with_reason`] within the HTLC's timeout, the HTLC will
+ /// be automatically failed.