while I triggered Fota from server i got in response of /5/0/1,4.06- Not acceptable and after that i got in /5/0/5- value 4 which is error of “Loss Connectectivty” and after that device crash, got blue screen error

LwM2M over CoAP makes the LwM2M objects/resources accessible trough CoAP paths that are exclusively numeric. Why were numeric paths chosen? In CoAP, each segment of the path is encoded as its own instance of the Uri-Path option, so I first thought that numeric path segments were potentially more efficient to encode than path segments that contained arbitrary strings. In CBOR for example, the encoding of small numbers (-24 to 24) can be just a single byte long, while small strings have at least one byte overhead, plus the character bytes. However, CoAP specifies that the Uri-Path option contain a string (see Table 4 in section 5.10), so there is no encoding benefit at all (rather, by limiting to strings representing integers, there are less very short path options available). So why was it chosen then?