This is description of mode 64 , Carry all the remaining value of the inbound message in addition to the value initially indicated in the new message what it means , new message refer to who ,value is not something that validator can rewrite , so what initially indicate means? we put some value there , and send message , what inbound message here refer to , is it mean incoming message or outgoing message , how they can indicate initially and then by mode it will change , or maybe we should guess all of them and hope we have correct guess

flag +1 it said Pay transfer fees separately from the message value , let say we have 3 smart contract which work together , this message value here is about action message (message after processing inbound message ) or just send_raw_message , is it apply for master contract or can be used down the road too

Let's say we are processing message with value 1.1 TON.
Our contract spends 0.1 TON for storage and computations and then sends message with value 3 TON and mode 64.

Message gets sent with value 4 TON.

flag +2 said Ignore any errors arising while processing this message during the action phase , if we ignore errors what happen for state , bounce , commit , outgoing message , all will be apply , ignored , some yes , some no ,

For internal message layout we have technical discussion , for external , it said it does not need to be as standardized (written by different developers and managed by different owners) , my question is about how we should deal with op code . In TL-B , we have arbitary hex number act as tag or id of schema (after #), but no where we have any clue(or maybe I can not find) that this is op code , and we can access it by calling op = msg.load_unit(32) (simplified) ,I mean it seems it is convention , and used every where , but why this is not mentioned anywhere ,All information we have is this note : In general, an external message begins with a 256-bit signature (if needed), a 32-bit req-seqno (if needed), a 32-bit expire-at (if needed), and possibly a 32-bit op and other required parameters depending on op. The layout of external messages does not need to be as standardized as that of internal messages because external messages are not used for interaction between different smart contracts (written by different developers and managed by different owners). from this page