Paths used to be threaded through every function as base_path kwargs, defaulting to cwd — a holdover from when storied ran out of the repo root. That pattern stopped making sense once worlds/ and players/ moved to ~/.storied/, and it meant a forgotten kwarg in a test would silently write to the user's real home dir. Centralize all filesystem roots in storied.paths as module globals, configured once at CLI startup via configure(). Everything downstream reads through getters (world_path, player_path, etc.). Drop base_path from every library function, class, and tool wrapper; delete the StorageRoot() dep and the base_path field on ToolContext. While the paths layer was already in pieces, add a third content layer for personal homebrew at ~/.storied/rules/. Priority is world > user > shipped — a campaign override beats your homebrew which beats the stock SRD. The vector index tags rows by source (srd/user/ world) and recall(scope="rules") now covers all three, so dropping a spell into ~/.storied/rules/spells/ shows up across every campaign after a `storied index rebuild`. Test isolation is now an autouse fixture that points paths at tmp_path for every function, with STORIED_HOME belt-and-suspenders for any subprocess that re-enters storied. The sandbox mode keeps user homebrew accessible — only worlds/players move to the tempdir. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>