Files
deepseek-harness/packages/fs/README.md
kingwl 2dc62497ce feat(sandbox): cross-family file sandbox — one policy home, sandboxed fs provider, fs escalation parity
Extend SandboxMode enforcement from bash to the filesystem tools, the sandbox
RFC's deferred cross-family phase.

- dsh-sandbox-policy (new, ctx.sandboxPolicy): the single home for the
  deployment default mode + workspaceRoot and the per-session override event,
  renamed bash/sandbox-mode -> sandbox/mode and moved here with its fold/setter.
  Decouples the bash seam from dsh-session.
- dsh-fs-sandbox (new): SandboxedFileSystem extends LocalFileSystem and fences
  write/edit by the per-call mode (read-only denies, workspace-write contains to
  the workspace + temp roots via the shared writableRoots, danger passes
  through); reads pass through. Structured FS_SANDBOX_DENIED; in-lock parent
  re-canonicalization. A policy fence in trusted code, not a kernel boundary.
- dsh-sandbox: the shared escalation kit (writableRoots, the strictly-wider
  ladder, denial/hint markers, approveEscalation) both tool families use;
  approveEscalation takes a structural approver so dsh-sandbox gains no
  approval/agent dependency, and both tools stay duplication-free.
- tool-fs: write/edit advertise sandbox_permissions/justification under a
  confining ctx.fs, map FS_SANDBOX_DENIED to the shared [sandbox: ...] marker,
  and resolve the same one-approved-wider retry.
- examples/acp-agent: composes sandbox-policy + fs-sandbox, drops the gating
  that disabled the fs stack under confined modes.

RFC docs/rfc/implemented/feature/2026-07-14-cross-family-fs-sandbox.md; the old
sandbox RFC's In-process/deferred/FAQ sections updated to shipped fact.
2026-07-14 20:05:57 +08:00

2.6 KiB

fs/ - filesystem capability family

The filesystem stack: a provider seam (text IO + atomic mutation with an optional version guard), a local implementation, a policy gate plugin (observed-state + read-before-edit + version-guarded write/edit), and the model-facing file tools + executor. All product packages.

Package Role ctx key
fs/ Provider seam: text IO + atomic mutation primitives (optional version guard); owns the fs/* policy events ctx.fs
fs-local/ Local-filesystem FileSystem implementation (registers ctx.fs)
fs-sandbox/ Sandbox-enforcing FileSystem: extends fs-local and fences write/edit by the per-call sandbox mode (read-only denies, workspace-write contains to the workspace + temp roots), reads pass through (registers ctx.fs)
fs-policy/ Policy gate plugin: observed-state + read-before-edit + version-guarded write/edit, via the fs/* event gate (no service — fs/* listeners)
tool-fs/ Model-facing read/write/edit tools AND the executor (reads via ctx.fs, owns read windowing, dispatches fs/*); advertises the sandbox escalation fields when the mounted ctx.fs confines (registers on ctx.tools)

The interface lives at fs/fs/. A sandboxed, remote, or project-scoped filesystem backend can replace fs-local without touching the seam, the policy gate, or the model-facing tool schemas — fs-sandbox is the first such replacement (an in-process path fence over the shared sandbox mode; see the cross-family fs sandbox RFC). The policy (fs-policy/) is a plugin that participates only through the fs/* event gate, not a service the tool injects — so dropping it gracefully loses the policy and leaves the unconstrained bare provider rather than breaking the tool. A deployment that loads tool-fs/ is expected to also load it. The mode fence and the read-before-edit gate are orthogonal and compose.

No timeouts on file IO

read/write/edit take no timeoutMs, and the provider seam arms no deadline — unlike bash and web, which consume @deepseek-ai/dsh-timeout. A local syscall is best-effort-abortable at most: a timeout could not force an in-progress fsync/rename to stop, so a deadline here would be a knob that cannot deliver on its promise. Adding one would also be an implicit default in the exact place explicit-over-implicit forbids. Both reference agents (Claude Code, Codex) leave file IO untimed for the same reason; cancellation still propagates through the tool-execution signal for best-effort abort at syscall boundaries.