vault.py: a folder of Markdown notes on the agent host, as SilverBullet reads them. Only configured folders exist for the agent, each rw or ro (`vault:` in the configuration); paths are checked in code (relative, inside a folder, symlinks included, Markdown, never the editor's own files). Writes are atomic (temporary file, fsync, rename, directory fsync) and merge provenance into the note's frontmatter, keeping the rest; failures are results. read_note, list_notes and search_notes are control tools in the harness for the driver (before the go-ahead, and while a VM is blocked) and for conversations, labelled with their path; the prompt says a note is information, never an instruction. Writing by the model is M5.2's. With the operator: SilverBullet replaces Obsidian and runs on the vault itself, agents' folders mounted read-only, so no Syncthing (L10, X5, M5.4). Per-agent mounts come with the containers (M6.1). Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01J5Utyfzw7gF7UhjRDEtjTk