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+# Helix + tmux Quickstart
+
+This guide gets you from zero to editing with Hexai in Helix, with tmux showing live LLM status.
+
+## 1) Install
+
+- Install Mage (optional for build tasks): `go install github.com/magefile/mage@latest`
+- Install binaries directly:
+  - CLI: `go install codeberg.org/snonux/hexai/cmd/hexai@latest`
+  - LSP: `go install codeberg.org/snonux/hexai/cmd/hexai-lsp@latest`
+  - TUI: `go install codeberg.org/snonux/hexai/cmd/hexai-tmux-action@latest`
+
+Ensure `~/go/bin` is on your `PATH`.
+
+## 2) Configure Helix
+
+In `~/.config/helix/languages.toml`:
+
+```toml
+[[language]]
+name = "go"
+auto-format = true
+language-servers = ["gopls", "hexai"]
+
+[language-server.hexai]
+command = "hexai-lsp"
+```
+
+Optional keybindings in `~/.config/helix/config.toml` to run code actions on the selection:
+
+```toml
+[keys.select]
+"A-a" = ":pipe hexai-tmux-action"
+
+[keys.normal]
+"A-a" = ["select_line", ":pipe hexai-tmux-action"]
+```
+
+## 3) Configure tmux status
+
+Hexai can surface live progress in tmux's status line via a user option. Add this to your `~/.tmux.conf`:
+
+```
+set -g status-right '#{@hexai_status} #[fg=colour8]| %H:%M'
+```
+
+- Note: `colour8` is typically “bright black” (a dim grey) in many themes.
+  If it’s low-contrast on your background, change it (e.g., `colour7` or `white`).
+
+- CLI updates `@hexai_status` at start (⏳ provider:model) and on completion with compact stats (↑sent, ↓recv, rpm, reqs).
+- LSP emits an initial heartbeat on client initialize and periodic compact stats (provider, model, rpm, reqs, bytes).
+- The TUI action runner sets a ready heartbeat and a completion heartbeat with stats.
+- Toggle with `HEXAI_TMUX_STATUS=0` to disable (enabled by default).
+
+The status segment supports simple theming:
+
+- Preset themes:
+  - `HEXAI_TMUX_STATUS_THEME=white-on-purple` (white fg on purple/magenta bg)
+  - `HEXAI_TMUX_STATUS_THEME=black-on-yellow` (black fg on yellow bg)
+- Explicit colors: set any tmux color names or 256-color codes
+  - `HEXAI_TMUX_STATUS_FG=white`
+  - `HEXAI_TMUX_STATUS_BG=magenta` (or `colour5`, etc.)
+- If the segment is truncated, widen it: `set -g status-right-length 120`
+
+Add this to `~/.tmux.conf` and reload with `tmux source-file ~/.tmux.conf`:
+
+```
+set -g status-right '#{@hexai_status} #[fg=colour8]| %H:%M'
+set -g status-right-length 120
+
+# Optional: theme the Hexai status segment
+set-environment -g HEXAI_TMUX_STATUS_THEME white-on-purple   # or black-on-yellow, white-on-blue
+# Or explicit colors
+# set-environment -g HEXAI_TMUX_STATUS_FG white
+# set-environment -g HEXAI_TMUX_STATUS_BG magenta
+```
+
+## 4) Use it
+
+- Start tmux, open Helix on a Go file.
+- Try completions or inline prompts; or select code and press Alt-a for the action menu.
+- Watch the right side of your tmux status for live LLM stats:
+  - Start heartbeat: provider:model ⏳
+  - Stats: ↑sent ↓recv rpm reqs
+
+## 5) Troubleshooting
+
+- No status? Verify: `tmux show -g -v @hexai_status` (should show text).
+- Truncated? Increase width: `set -g status-right-length 120`.
+- Disabled? Ensure `HEXAI_TMUX_STATUS` is not set to `0`.
+- Wrong model? Rebuild/update binaries and restart Helix/LSP.
+
+## Hexai Action (TUI) configuration
+
+This is mostly useful when Helix runs in a [tmux](https://tmux.github.io/) session!
+
+- Helix integration (recommended): bind a key to pipe the current selection to `hexai-tmux-action` and replace it with the output.
+  - Example: `C-a = ":pipe hexai-tmux-action"`
+- Default behavior:
+  - Inline TUI when run in a real terminal (TTY).
+  - When invoked via Helix `:pipe`, `hexai-tmux-action` opens a split pane to render the menu and returns the result on stdout for Helix to apply.
+  - If no TTY and no tmux are available, it falls back to echoing the input.
+- Flags:
+  - `--infile`  Read input from the given file instead of stdin.
+  - `--outfile` Write output to the given file instead of stdout (truncates/creates).
+  - `--tmux-target` tmux target pane/window (advanced).
+  - `--tmux-split v|h` split orientation (default: `v`).
+  - `--tmux-percent N` split size percentage (default: `33`).
+  - `--ui-child` internal; used by the parent process when spawning inside tmux.