Browsing tool in Assistants API

How can we use function calling to achieve the same browsing functionality in the Assistants API as the official ChatGPT app?

I have such problems when trying to scrape a large page:

Error: 400 'tool_outputs' too large: the combined tool outputs must be less than 512kb.

Do we need to use Vector Storage for this?

How does ChatGPT internally manage the context window size for such tasks?