Agents leave scraps everywhere: logs, diffs, notes, results. coat collects them, records where each one came from at the moment it was made, and stitches them into a single self-contained HTML page. Provenance lives in an append-only hash-chained ledger, every source keeps its own patch color, and anywhere two agents covered the same ground is marked as a seam, open until a person says it is settled. Wires itself into Claude Code's hooks so a session collects itself.