How provenance shows up in this material Provenance here means the ability to trace where each piece of text in a document came from — specifically, whether a human wrote it or an AI agent wrote it. It is the original motivating problem behind Proof, Every's collaborative editor: as planning docs get written increasingly by agents (like Notion agents producing 2026 plans), how do you tell what a human actually wrote, thought about, and stands behind? How it works in practice The first version of the tool was a Mac app with a colored gutter that marked authorship directly in the text: - purple = AI-written text - green = human-written text The live demo showed the same idea in the web editor: agents joining a document write content marked purple, while human edits show up green. For one team member this was the deciding factor — in Google Docs it was clunky, even impossible, to track what he wrote versus what the agent wrote. Provenance also survives into everyday workflows: a writer deliberately keeps his drafting mostly his own words by only letting the agent draft after he has monologued into the doc, so the colored record reflects his voice. Watch the turning point when provenance-tracking evolved into real-time collaboration. [moment: 397] Beyond colors: where writing came from As the product matured, the team widened provenance into a broader mission. Proof's job is not to organize documents — it is to communicate about writing, ideas, and where writing came from. Once a doc is mature, it graduates to heavier tools like Notion; Proof remains the place where authorship and ideas are visible while the writing happens. - Provenance = tracing the origin of text: whether a human or an agent wrote each part of a document. - It was the original motivation for Proof, driven by agent-generated planning docs. - The implementation is color-coded authorship: purple for AI, green for humans. - Provenance helps writers stand behind their work and track their own contributions versus agent contributions. - The idea grew into Proof's broader purpose: communicating where writing came from.