Explain what is primitive model
The primitive model means that the token will interact with the XY Assets bridge by lock / unlock manner on the chain. If the primitive model is adopted on the chain, while users bridge the token to other chains, the token will be locked to the XY Assest bridge contract deployed on the chain. While users bridge back the token from other chains, the tokens will be unlocked from the XY Assets bridge contract and sent to the user.
This mode is applicable to project already issued their tokens on multiple chains and intend to bridge the token among these chains. XY Assets bridge won't be given the mining permission of the tokens, and the project needs to provide the original liquidity on the source chain and the target chain in the contract to meet the initial user needs.