Web pages are not what Claude wants to read
Anthropic's training corpus is heavy on documentation, README files, and structured Markdown — not on rendered HTML with its inline styles and div nesting. Paste a Stack Overflow answer's HTML and Claude has to mentally re-derive what's code, what's prose, and what's the answerer's sidebar widget. Paste the same answer as Markdown and Claude sees a question, an answer, fenced code blocks, and prose — the way it was trained to read.
The Projects-as-knowledge-base pattern
Claude Projects is the highest-leverage feature for web research workflows. Convert the URLs you reference repeatedly — your team's internal wiki pages, a competitor's docs, a vendor's API reference — and drop the Markdown into a Project's knowledge base. Every conversation in that Project starts with structured, citable web content, and Claude will quote sections accurately ("from Section 3 of the converted page…") instead of hallucinating URLs.