d753660d66
The writeText comment still said a null `before` (a create or an undiffable binary file) means "a consumer renders no result-time diff, only the call-time whole-file card." That is stale since write's presentResult renders a whole-file diff for a null before-image. Correct it: a null `before` gives no contextual-hunk basis, so the consumer falls back to a whole-file diff — the tool still renders a result diff card, not the raw result text.
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-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/*) |
(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. 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.