A mistyped or unsupported flag (e.g. --automation-write-roots) used to be
dropped silently, so the app started unconfined. It now exits 2 with
'unknown option', like a bad automation root. A bare -- ends the options.
Adds a desktop control-channel test that file.save / file.saveAs outside the
write root are refused and create nothing, while saves inside succeed, and
documents that the root flags arrived in 0.7.0 (0.6.0 ignores them).
- `figcraft-cli mcp --automation-read-root DIR --automation-write-root DIR` (each repeatable, `--flag=DIR` works too). When either is given, every file an agent's tool call reads must lie inside a read root or a write root, and every file it writes inside a write root. Anything else is an ordinary tool error (`automation path rejected: … is outside the folders that may be written: …`); nothing is written and the server keeps serving. Without the flags nothing changes.
- The desktop app takes the same flags (`figcraft --control PORT --automation-read-root DIR …`) and confines every control request and every frame of every window to them, so `figcraft-cli mcp --attach` drives a confined app. `--attach` together with the flags is a usage error, because the app runs the commands and only the app can confine them.
- New engine module `crates/engine/src/file_access.rs`: `Roots` (resolution and comparison), a thread-scoped `confined(roots, f)`, and the file primitives (`read`, `read_capped`, `open`, `metadata`, `read_dir`, `write` (atomic), `create_dir_all`, `exists`, `is_dir`). Every engine file access now goes through it. `crates/engine/clippy.toml` denies `std::fs::*`, `File::open/create`, `OpenOptions::open`, `Path::exists/is_file/is_dir/metadata/read_dir/canonicalize` and `figcraft_format::{write_file_atomic, save_file, load_file}` everywhere else in the engine, so a command added later is confined without a check of its own.
- `ui.screenshot` and `ui.render` return the PNG as base64 `data` when no `path` is given (before, `ui.screenshot` wrote `figcraft-screenshot.png` in the working directory and `ui.render` required a path). The attached MCP backend uses that, so it no longer writes and deletes temporary PNGs, and a confined app needs no exemption for them.
- `initialize`'s `instructions` name the folders the agent may read and write.
- `figcraft-cli` options may be given more than once (`Args::values`); single-valued options keep the last value, as before.
- Docs: `docs/mcp.md` › Confining file access (options, semantics, coverage, resolution, limits), `docs/control-protocol.md` › Confining file access and the optional `path` of `ui.screenshot` / `ui.render`, `docs/cli.md`, `figcraft-cli --help`, and the Automation line plus a revision row in `docs/target-app-parity.md`.
Fixes#715, fixes#481.
- Browser client (step 4): the web build joins sessions a desktop app hosts
through the browser's WebSocket API (web-sys, binary frames, the same
message encoding). Its connection logic is a target-independent state
machine (collab-net driver.rs): hello on open, changes and presence held
until the welcome, throttled presence, keep-alive pings, a silent host
counted as dropped, reconnect with backoff, final refusals. Tested natively
against a scripted socket and a real host over loopback. Hosting stays
desktop-only (LiveLink::can_host; collab.peers canHost). https pages are
told up front that they can only reach ws:// sessions on this computer.
- Shared join logic (join.rs: GuestConfig, outcomes, taking in host messages)
and transport limits (limits.rs) used by the native guest and the browser.
- Invite links: `figcraft figcraft://join?...` joins on start (a bad link
opens the Join dialog with it); file:// arguments are paths. Windows
registers a per-user figcraft:// opener (HKCU\Software\Classes\figcraft)
behind a Registry trait (tests use a fake): collab.registerLinks {on?} and a
Preferences checkbox, default on for installed builds, never for builds
from source. macOS Info.plist declares CFBundleURLTypes; the Linux desktop
entry declares x-scheme-handler/figcraft and passes %U.
- Join dialog: Escape closes it and no longer reaches the canvas (selection
kept); its field has the keyboard when it opens.
- Docs: collab-protocol (browser client, links, mixed content), mcp,
control-protocol, README, web hosting notes, collaboration wording in the
progress docs (numbers unchanged).
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
bflatastic