Skipping registered tools

[SimonCao1207]

Is there a specific reason why persistent storage of tools' registered info in tools.json is emptied every time rerun ?
why not skipping already registered tool to save some LLM calls ? I can submit a PR if this is reasonable.

[phamdinhkhanh]

I design tools will be re-initialized each time we construct an instance of Agent because it ensures this tool list will be updated according to the last new Agent. I will add new parameters flagging whether overriding the old tools list or not.