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+# PRD — OpenCode CLI Install + Engine Bootstrap (OpenWork)
+
+## Summary
+
+OpenWork currently requires the `opencode` CLI to already be installed and available on the user’s PATH. This is a major onboarding cliff for non-technical users.
+
+This PRD proposes a **first-run “Engine Setup” step** in Host-mode onboarding that:
+
+1. Detects whether `opencode` is available (and compatible)
+2. If missing, offers a **guided one-click install** (macOS/Linux) or clear manual instructions (Windows)
+3. Verifies install success and then starts `opencode serve` reliably, even when PATH changes don’t propagate into GUI apps
+
+The goal is to make “fresh install → first successful task run” achievable without opening a terminal.
+
+## Problem
+
+Today, Host mode fails with a generic spawn error when OpenWork can’t find `opencode`.
+
+- Users don’t know what `PATH` means.
+- Users don’t know where to install OpenCode.
+- Even if we run an installer that modifies shell rc files, **GUI apps won’t automatically inherit that updated PATH** (macOS in particular).
+
+This conflicts with OpenWork’s success metric: **< 5 minutes to first successful task on fresh install**.
+
+## Goals
+
+- Detect missing OpenCode engine **before** the user hits “Start”.
+- Provide a safe, guided install flow with explicit consent.
+- Show clear progress + logs (download, unpack, verification).
+- Make the engine start reliably after install (avoid “it’s installed but OpenWork can’t find it”).
+- Keep parity with OpenCode primitives: still run `opencode serve`.
+
+## Non-goals
+
+- Bundling `opencode` into OpenWork releases (possible future work).
+- Implementing an auto-updater for `opencode` (future).
+- Supporting fully offline installs (we can provide guidance, but not guarantee).
+
+## Current Architecture (Constraints)
+
+- Tauri backend starts engine by spawning `opencode serve …`.
+- UI connects using `@opencode-ai/sdk/v2/client`.
+- The Tauri app is a GUI process; shell rc changes won’t necessarily affect it.
+
+## Proposed UX
+
+### Where this lives
+
+Host onboarding adds a step after folder selection:
+
+- **Engine Setup**
+  - Status: Checking… / Missing / Installing… / Installed
+  - Primary action: Install OpenCode (if missing)
+  - Secondary: View manual install instructions
+  - Tertiary: “I already installed it” → re-check
+
+### Flow A — `opencode` already available
+
+1. Engine Setup runs a check.
+2. If `opencode` is found and compatible:
+   - Show “OpenCode found: vX.Y.Z”
+   - Continue onboarding.
+
+### Flow B — `opencode` missing
+
+1. Engine Setup detects `opencode` cannot be executed.
+2. Show:
+   - Explanation: “OpenWork needs OpenCode installed to run tasks locally.”
+   - What it will do: “Download and install the OpenCode CLI to your user directory.”
+   - A clear consent affordance.
+
+**Buttons**
+- Primary: **Install OpenCode**
+- Secondary: Manual install
+- Secondary: Retry check
+
+### Flow C — Guided install succeeds
+
+1. OpenWork runs the installer.
+2. UI streams installer output in a collapsible log drawer.
+3. After completion:
+   - OpenWork re-checks the engine.
+   - If found, enables **Start Engine**.
+
+### Flow D — Guided install fails
+
+1. UI shows “Install failed” with:
+   - short reason (first stderr line)
+   - “Copy logs”
+   - “Manual install” instructions
+   - “Retry”
+
+### Flow E — Installed but not on PATH
+
+This is common if installation adds `~/.opencode/bin` to shell rc files.
+
+OpenWork should:
+
+- Search known install locations (see “Engine discovery”) and use an **absolute path** to run `opencode`.
+- If found outside PATH, show:
+  - “OpenCode installed at `~/.opencode/bin/opencode`”
+  - Optional action: “Add to PATH” (manual instructions; don’t silently edit dotfiles).
+
+## Proposed Technical Approach (No Implementation Yet)
+
+### 1) Engine discovery (“doctor”)
+
+Add a Tauri command to check engine availability and return structured info:
+
+- `inPath`: boolean
+- `resolvedPath`: string | null
+- `version`: string | null
+- `supportsServe`: boolean
+- `notes`: string[]
+
+**Discovery order**
+
+1. Try `opencode --version` (PATH)
+2. Try known paths:
+   - `~/.opencode/bin/opencode` (matches upstream install script)
+   - `/opt/homebrew/bin/opencode` (Homebrew Apple Silicon)
+   - `/usr/local/bin/opencode` (Homebrew Intel)
+   - Linux common paths (`/usr/bin/opencode`, `/usr/local/bin/opencode`)
+   - Windows common paths (TBD)
+
+3. If `opencode` is found, validate `serve` support:
+   - `opencode serve --help` (exit code 0)
+
+### 2) Guided install
+
+**Recommended approach (macOS/Linux):** run the upstream install script with explicit consent.
+
+Candidate URLs:
+
+- `https://opencode.ai/install` (if this is the canonical stable redirect)
+- `https://raw.githubusercontent.com/opencode-ai/opencode/refs/heads/main/install` (as documented upstream)
+
+Execution strategy (conceptual):
+
+- Run via `bash -lc "curl -fsSL <url> | bash"`
+- Capture stdout/stderr and stream to the UI
+- Allow choosing a pinned version (advanced): `VERSION=x.y.z`
+
+**Important:** the install script currently writes to `~/.opencode/bin` and may edit shell rc files to add PATH. OpenWork must not rely on that PATH change.
+
+**Windows:** do not attempt `curl | bash`.
+
+Options:
+
+- Manual instructions only (v0)
+- Or a native PowerShell installer (future) that downloads a release asset and stores it under `%LOCALAPPDATA%\\OpenCode\\bin` and uses that absolute path
+
+### 3) Engine start should accept a resolved path
+
+Instead of always `Command::new("opencode")`, engine start should prefer a resolved path from discovery.
+
+This avoids the “installed but not on PATH” trap and improves reliability on macOS.
+
+### 4) Permissions + Safety
+
+Running an installer is sensitive.
+
+Requirements:
+
+- No silent remote code execution.
+- Show the exact command that will run.
+- Provide a “View script” action (fetch and display) before install.
+- Clear opt-out path (manual install instructions).
+
+### 5) Telemetry / Diagnostics (Optional)
+
+Local-only diagnostics artifact:
+
+- engine discovery result
+- installer logs
+- final engine start result
+
+Exportable by the user to include in bug reports.
+
+## Manual install instructions (UI copy)
+
+OpenWork should show OS-specific instructions with copy buttons.
+
+Example:
+
+- macOS (Homebrew): `brew install opencode-ai/tap/opencode`
+- macOS/Linux (script): `curl -fsSL https://opencode.ai/install | bash`
+- Linux (script fallback): `curl -fsSL https://raw.githubusercontent.com/opencode-ai/opencode/refs/heads/main/install | bash`
+
+## Acceptance Criteria
+
+- Fresh machine with OpenWork installed but no `opencode`:
+  - User can complete guided install (macOS/Linux) without terminal.
+  - OpenWork verifies engine availability and can start Host mode.
+- If guided install fails:
+  - User sees a clear error, can copy logs, and sees manual instructions.
+- If `opencode` is installed outside PATH:
+  - OpenWork still finds and runs it via absolute path.
+
+## Open Questions
+
+- What is the minimum supported OpenCode server version for this OpenWork release?
+- Is `https://opencode.ai/install` the canonical stable installer URL we want to bless?
+- For Windows, do we want a v0 “manual only” stance, or a PowerShell installer?
+- Should OpenWork ever modify shell rc files, or only provide instructions?