BING_COPILOT asks the Copilot chat at copilot.com, with web search always on and no account or login involved.
Request
Response
Shopping questions often cite no page and return product cards instead, so
sources: [] is a normal answer. Each shoppingCards entry holds products, and product positions run across all cards. A product keeps Copilot’s review (a summary of what buyers say and the stores it came from), prosAndCons and curationInfo; each is null when Copilot has none. In images, url is the page the image belongs to and image is the image file; in videos, url is the watch page.
For example:
include.markdown, markdown places the image carousel as  lines where Copilot shows it, and each video as a linked thumbnail.
Include flags
searchQueries, ads and shopping have no effect. analysis is rejected with 422 VALIDATION_ERROR and html with 422 EVIDENCE_UNSUPPORTED. See Markdown and raw responses.