How Proof of Origin Shows Up in This Material Proof of Origin is the original form of what became the editor Proof. In this channel's material, it appears as a Mac app built at Every to solve a provenance problem: when AI agents produce documents, how do you know which lines a human actually wrote — and actually stands behind? [^01a0f15a-a8aa-793c-9ae2-1d1a1ab07374@327] [^01a0f15a-a8aa-793c-9ae2-1d1a1ab07374@351] The idea emerged during Every's 2026 planning exercise, when Notion agents turned leadership interviews into plan docs. CEO Dan questioned whether a colleague had really read every line of an AI-generated growth plan — so the team built a gutter on the side of the editor as a visual signal of authorship: - Purple for AI-written text - Green for human-written text [^01a0f15a-a8aa-793c-9ae2-1d1a1ab07374@373] [^01a0f15a-a8aa-793c-9ae2-1d1a1ab07374@386] Using the app revealed something simpler than authorship highlighting: the killer feature is just being able to share — letting a colleague and their agent read and comment on a doc. That insight drove the pivot from the Mac app to Proof, a live collaborative, web-based document where humans and agents edit together, leave comments, and do track changes. [^01a0f15a-a8aa-793c-9ae2-1d1a1ab07374@397] [^01a0f15a-a8aa-793c-9ae2-1d1a1ab07374@407] [^01a0f15a-a8aa-793c-9ae2-1d1a1ab07374@431] The authorship gutter still carries through to the current product, keeping the original question — what was human-written, what was agent-written, and who stands behind it — visible. [^01a0f15a-a8aa-793c-9ae2-1d1a1ab07374@386] - Proof of Origin was a Mac app at Every, built to make AI vs. human authorship visible. - Its signature feature was the purple/green gutter: purple for AI-written text, green for human-written text. - Sharing, not highlighting, proved to be the killer feature — driving the pivot into the live collaborative editor Proof. - The provenance idea behind Proof of Origin persists in the current product.