Files
sjw1231 cc2718bede fix(fs): address review of the shipped mutation defaults
A new Agent Note owns the shipped defaults and the original apply_patch note
keeps its opt-in decision with a supersession link; the policy README, the
tool-catalog note, the filesystem page, and the fs group README state the
current defaults without evaluation figures. The PTC overlay sets
`applyPatch: false` so the SDK and Desktop PTC tool sets match without a
parity exception; the fixed-budget compaction scenarios pin the tool set in
their live patches too; the apply-patch composition drops its no-op override.
The upgrade guide scopes the change to base-backed profiles, the README
refusal example is one every composition can produce, the integration suite
names its deployments by guard, and the keyless SDK smoke edits a file the
model never read through the shipped profile.
2026-10-29 21:19:14 +08:00

3.8 KiB

description, kind
description kind
The filesystem package group: the ctx.fs provider contract, local and sandbox-enforcing backends, the read-before-edit policy plugin, and the model-facing file and search tools. package-group

packages/fs

English | 中文

Summary

The fs/ group gives agents durable, policy-governed access to files: the ctx.fs service contract in fs/, the host-filesystem and sandbox-enforcing backends in fs-local/ and fs-sandbox/, the read-before-edit policy in fs-observation-policy/, and the model-facing tools in tool-fs/ (read, read_image, write, edit, apply_patch) and tool-fs-search/ (glob, grep). A deployment mounts one backend, optionally loads the policy for freshness-guarded mutations, and registers the tool packages the model should see; backends swap without touching the tools or the policy. File I/O takes no timeout by design: a deadline would kill work the OS still finishes, so cancellation is a best-effort signal at syscall boundaries.

Table of Contents


Packages

The packages below provide filesystem access and patch parsing; the subsystem reference owns the exhaustive contracts and the error taxonomy.

Package Role ctx key
fs/ ctx.fs service contract: execution-world paths, bounded text I/O, and atomic mutations with an optional version guard ctx.fs
fs-patch/ Pure Codex-style patch parsing and hunk application none
fs-local/ Host-filesystem backend: reads, writes, edits, patches, deletes, and moves real files on the local machine registers on ctx.fs
fs-sandbox/ Sandbox-enforcing backend: fences every mutation by the per-call sandbox mode while reads pass through registers on ctx.fs
fs-observation-policy/ Read-before-edit policy: records observed presence or absence and guards mutations through the fs/* events fs/* listeners
tool-fs/ Model-facing read, read_image, write, edit, and apply_patch tools plus their executor registers on ctx.tools
tool-fs-search/ Model-facing glob and grep discovery tools backed by the packaged ripgrep binary registers on ctx.tools
tool-str-replace-editor/ Standalone str_replace_editor tool: view, create, str_replace, and insert over ctx.fs registers on ctx.tools

The policy is a plugin, not a service the tools inject: removing it leaves the bare provider's unconditional mutation behavior instead of breaking the tools. The mode fence in fs-sandbox and the read-before-edit gate compose. tool-fs-search deliberately does not extend the provider contract — search is a process-backed ripgrep workflow, so filesystem backends stay free of a universal search API.


Start with the subsystem reference for the shared vocabulary and error taxonomy, then the decisions that shaped the family.

Dev Note

Working context for maintainers — click to expand

None.