# AGENTS.md
## Cursor Cloud specific instructions
**Product:** `mdiff` (crate name `mutiny-diff`) — a single-binary Rust TUI for reviewing git diffs and sending structured feedback to coding agents.
**Rust toolchain:** Pinned to `1.93.1` via `rust-toolchain.toml`. The toolchain is auto-installed by `rustup` when any `cargo` command is run.
### Build, lint, test
All commands match CI (see `.github/workflows/ci.yml`):
| Build | `cargo build` |
| Format check | `cargo fmt --all --check` |
| Lint | `cargo clippy --all-targets -- -D warnings` |
| Test | `cargo test` |
| Run | `cargo run` (or `cargo run -- <args>`) |
### Required checks (must pass)
- `cargo fmt --all --check`
- `cargo clippy --all-targets -- -D warnings`
### Running the application
`mdiff` is a TUI that must be run inside a git repository with a real terminal (not a pipe). It diffs the working tree against HEAD by default. To test it you need uncommitted changes or pass a target ref (e.g. `cargo run -- main`).
### Native dependencies
The build requires `cmake`, `pkg-config`, and a C compiler (`cc`/`gcc`). These are pre-installed in the Cloud VM. The `git2` crate vendors OpenSSL and libgit2, so no system OpenSSL dev headers are needed.
### Clipboard
The `arboard` clipboard crate requires a display server or clipboard provider. On the headless Cloud VM, clipboard operations (`y` to copy prompt) will fail gracefully — this does not affect core diff review functionality.