th-4d9ee1: sandbox posture for a personal assistant#241
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User-authorized (2026-07-20): Brent explicitly directed this change and its landing after reviewing the tradeoff. The Seatbelt profile confined writes to the workspace, which made Big Smooth ineffective as a personal assistant: it could not edit ~/.zshrc or ~/.config, and burned ~30 turns failing to place a file in ~/.config. A path-based write jail cannot tell a benign config edit from a harmful one -- it only sees paths. So the jail is replaced by permit-by-default plus targeted denies for the guarantees that must hold unconditionally: credential stores, ~/Library/LaunchAgents, and .git/hooks + .git/config. The git denies are path regexes rather than workspace subpaths, so they cover every checkout on the machine. Intent-level judgement moves to the behavioural layers: the engine DenyPolicy circuit-breakers (which no AutoMode can downgrade) and the Narc LLM judge. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_015ZctFb4oiWoJraHN2db1nX
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Problem
The macOS Seatbelt profile confined writes to the workspace. That made Big Smooth ineffective as a personal assistant — it couldn't edit
~/.zshrcor anything under~/.config, and in one session burned ~30 turns failing to place a poster file in~/.config.A path-based write jail can't distinguish "edit my shell rc" from "exfiltrate my SSH key". It only sees paths.
Change
Permit writes by default, and keep kernel denies only for guarantees that must hold unconditionally even against a fully-hijacked shell:
~/.ssh,~/.aws,~/.config/gh,~/.config/gcloud,~/.kube,~/.docker,~/.gnupg,.netrc,~/.smooth/auth,providers.json~/Library/LaunchAgents— a login agent written here would later execute outside the sandbox.git/hooks+.git/config— execution re-entryThe git denies are path regexes, not workspace subpaths. Once writes are permitted broadly, a workspace-scoped deny would leave a hook plantable in every other checkout on the machine. Covered by a regression test that asserts the deny holds in an unrelated repo.
Intent-level judgement moves to the layers that can actually see intent: the engine DenyPolicy circuit-breakers (which no AutoMode can downgrade) and the Narc LLM judge.
Verification
cargo test -p smooai-smooth-tools→ 105 passed, 0 failedcargo fmt --checkclean$HOMEwrite now succeeds, while a write under~/.sshis still kernel-denied (asserted by exit code and by the file's absence)Note
This deliberately widens what the agent may write. It was directed and authorized by the repo owner after reviewing the tradeoff; the security posture shifts from path-jailing to behavioural gating rather than being removed.
Pearl: th-4d9ee1
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