1 # CLAUDE.md
2
3 This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
4
5 ## What this is
6
7 `sigit` ("siGit Code") is a single Rust binary: a local-first AI coding agent that runs LLM
8 inference on-device (via the `onde` crate / GGUF models) or against a hosted/OpenAI-compatible
9 endpoint. It exposes itself two ways from the *same* binary, chosen at startup by whether stdin
10 is a TTY:
11
12 - **ACP mode** (stdin not a TTY): speaks the Agent Client Protocol over stdio for editor
13 integration (Zed, VS Code ACP Client). Cross-platform.
14 - **Interactive terminal mode** (stdin is a TTY): a full-screen ratatui chat UI. **Unix-only**
15 it relies on fd redirection to keep logs out of the TUI, so Windows gets ACP mode only.
16
17 Before the TTY/ACP split, `main` also dispatches the account subcommands `sigit login`,
18 `sigit logout`, `sigit whoami` (see `src/main.rs` `main()`).
19
20 ## Build / test / lint
21
22 ```sh
23 cargo build # debug build
24 cargo build --release # release binary at target/release/sigit
25 cargo run # launches interactive TUI (stdin is a TTY)
26 cargo test # CI runs: cargo test --locked --target <target>
27 cargo clippy --tests -- -D warnings # CI gate: clippy is -D warnings on all 4 targets
28 cargo fmt -- --check # CI gate (edition 2024)
29 ```
30
31 CI (`.github/workflows/ci.yml`) runs fmt + clippy + test across four targets:
32 `aarch64-apple-darwin`, `x86_64-apple-darwin`, `x86_64-unknown-linux-gnu`,
33 `x86_64-pc-windows-msvc`. Clippy is `-D warnings`, so warnings fail the build.
34
35 Run a single test: `cargo test <test_name>`.
36
37 ## Critical platform constraint: `#[cfg(unix)]` dead code
38
39 The interactive client, the `InferenceBackend` seam (`backend.rs`), and provider resolution
40 (`provider.rs`) are wired up **only** through `#[cfg(unix)]` code paths. On Windows the binary
41 runs ACP-only and drives `onde` directly, so much of `backend.rs` and `provider.rs` is
42 legitimately unused there and the dead-code lint is suppressed *on non-Unix targets only*.
43
44 Consequence: code can pass clippy on macOS/Linux but fail on the Windows target (or vice versa).
45 When touching `backend.rs`, `provider.rs`, or the interactive path, keep the `cfg` gates intact —
46 don't "fix" an unused-warning by deleting code that's live on Unix.
47
48 ## Architecture
49
50 The agent loop is backend-agnostic. The flow: a turn (messages + tool specs) goes to an
51 `InferenceBackend`, which returns assistant text and/or tool calls; the loop executes tools and
52 feeds results back. Neither the loop nor ACP/TUI surfaces depend on a concrete backend.
53
54 - **`src/main.rs`** — entry point, mode dispatch, the full ACP `Agent` impl (session lifecycle:
55 new/load/fork/prompt/cancel, config options, slash-command advertisement), and the `SYSTEM_PROMPT`
56 (note: it bakes in smbCloud-specific context the agent should use when the repo is clearly
57 smbCloud, and stay general otherwise).
58 - **`src/backend.rs`** — the `InferenceBackend` trait and neutral types (`ToolSpec`, `ToolCall`,
59 `ToolResult`, `TurnResult`). Two impls: `LocalBackend` (on-device via `onde::ChatEngine`) and
60 `OpenAiBackend` (any OpenAI-compatible HTTP endpoint).
61 - **`src/provider.rs`** — decides *which* backend serves inference. Resolution order, first match
62 wins: (1) override via `OPENAI_BASE_URL`+`OPENAI_API_KEY` or active profile in
63 `~/.config/sigit/providers.toml`; (2) siGit Code Cloud when logged in; (3) on-device.
64 - **`src/tools.rs`** — agent tool schemas + execution: `read_file`, `create_directory`,
65 `list_directory`, `search_files`, `read_website`, `create_file`, `edit_file`, `delete_file`,
66 `run_command`. Add a tool in both the spec list and the execute `match`.
67 - **`src/chat.rs`** — the Unix-only ratatui TUI. Loading-spinner phase then chat; uses
68 `tokio::select!` to multiplex terminal events with streaming tokens.
69 - **`src/setup.rs`** — model cache location, local model discovery, selected-model persistence.
70 Must run (`setup_shared_model_cache`) *before* anything touches `ChatEngine`/`hf-hub`, since
71 those read env vars once at init.
72 - **`src/account.rs`** — siGit Code Cloud auth (`/login`, `/logout`, `/whoami`); authenticates
73 against the account API and stores a session token. Performs no console I/O.
74 - **`src/credentials.rs`** — local session-token store (TOML, `0600` on Unix).
75 - **`src/models.rs`** — model-picker types shared across platforms.
76
77 Slash commands (`/help`, `/models`, `/login`, `/logout`, `/whoami`, `/reload`, `/clear`,
78 `/status`) are advertised via `advertise_commands` in `main.rs` and handled in both the TUI and
79 ACP sessions.
80
81 ## Model cache (macOS)
82
83 On macOS the HF model cache lives in an App Group container shared with the siGit desktop app:
84 `~/Library/Group Containers/group.com.ondeinference.apps/models/`. Other platforms fall back to
85 `~/.cache/huggingface/`. The CLI reuses a model the desktop app already downloaded. First run
86 downloads a GGUF model (~1–2 GB) from Hugging Face.
87
88 ## Logging
89
90 In TTY (interactive) mode, *all* output — `log`, `tracing`, stray `println!` — is redirected to
91 `$TMPDIR/sigit.log` so the ratatui surface stays clean; the TUI holds a separate fd to the real
92 terminal. In ACP mode, stdout is reserved for protocol JSON and logs go to stderr. Control
93 verbosity with `RUST_LOG`.
94
95 ## Relevant env vars
96
97 `OPENAI_BASE_URL` / `OPENAI_API_KEY` (provider override), `SIGIT_API_URL` (account API base,
98 default `https://sigit.si`), `SIGIT_CLOUD_URL`, `SIGIT_CONFIG_DIR` (default `~/.config/sigit`),
99 `SIGIT_MODEL`, `HF_HOME` / `HF_HUB_CACHE`, `RUST_LOG`.
100
101 ## Releasing
102
103 Version lives in `Cargo.toml`. The binary is published to five registries via separate workflows
104 (`release-crates`, `release-github`, `release-homebrew`, `release-npm`, `release-pypi`); the
105 `npm/` and `pypi/` dirs hold the wrapper-package templates. Update `CHANGELOG.md` for releases.