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+This guide covers the day-to-day use of NVCurve, from launching the web UI to managing profiles and using the CLI.
+
+## First-Time Setup
+
+Before using NVCurve, always run the hardware compatibility check:
+
+```bash
+nvcurve setup
+```
+
+This verifies that your GPU and driver support the required NvAPI functions, performs a safe test write, and restores your GPU to its original state. Only proceed if the result is **Compatible**.
+
+## Web UI
+
+The web UI is the primary interface for curve editing and monitoring.
+
+### Launching the Web UI
+
+```bash
+nvcurve
+```
+
+This starts the backend server and opens your browser at `http://127.0.0.1:8042`.
+
+### Server Management
+
+```bash
+nvcurve serve start          # Start the web server
+nvcurve serve start --detach # Start in the background
+nvcurve serve status         # Check if the server is running
+nvcurve serve stop           # Stop the server
+```
+
+### Curve Editor
+
+The curve editor displays your GPU's V/F curve as an interactive graph with draggable points.
+
+| Action | How |
+|---|---|
+| Select a point | Click on it |
+| Multi-select | Shift+click to add/remove points |
+| Select all active points | Ctrl/Cmd+A |
+| Clear selection | Escape |
+| Edit a point | Drag it to stage a frequency offset |
+| Move multiple points | Drag with multiple points selected |
+| Exact value input | Select one point, press Enter |
+| Nudge ±1 MHz | Arrow keys (↑ / ↓) |
+| Nudge ±10 MHz | Ctrl/Cmd + arrow keys |
+| Step through points | Tab / Shift+Tab |
+| Box select | Shift+drag on the background |
+| Pan the graph | Drag on the background |
+| Zoom | Alt+scroll |
+
+### Point Table
+
+The point table provides a spreadsheet-like view of all curve points with their frequency, voltage, and offset values.
+
+| Action | How |
+|---|---|
+| Select a point | Click a row |
+| Toggle selection | Ctrl/Cmd+click |
+| Range select | Shift+click or drag across rows |
+| Select before/after | Click "Select Before" or "Select After" (appears for single selection) |
+
+### Toolbar
+
+The toolbar provides bulk operations:
+
+- **Global Offset Slider** — Appears when all active points share a uniform delta. Adjusts every point simultaneously.
+- **Flatten** — When two or more points are selected, flattens them to the anchor point's frequency. The anchor is the last explicitly clicked point (highlighted with an amber halo).
+- **Apply** — Commits staged changes to the GPU.
+- **Reset** — Clears all offsets back to zero.
+
+### Live Monitoring
+
+The monitoring panel shows real-time GPU metrics:
+
+- Voltage
+- Clock speed
+- Temperature
+- Power draw
+
+Data is streamed via WebSocket from the backend at a configurable poll interval (default: 1 second).
+
+### Multi-GPU
+
+When multiple NVIDIA GPUs are detected, a GPU selector dropdown appears in the status bar. Switching GPUs resets pending edits, selection state, and monitoring for the new target.
+
+## CLI Reference
+
+The CLI is designed for scripting, headless use, and quick operations. All write commands support `--dry-run` to preview changes.
+
+### Reading the Curve
+
+```bash
+nvcurve read                  # Condensed V/F curve
+nvcurve read --full           # All points including zeros
+nvcurve read --json           # JSON output for scripting
+```
+
+### Writing Offsets
+
+```bash
+# Preview changes without applying
+nvcurve write --global --delta 50 --dry-run
+nvcurve write --point 80 --delta 100 --dry-run
+
+# Apply changes
+nvcurve write --global --delta 50        # All active GPU points
+nvcurve write --point 80 --delta 100     # Single point
+nvcurve write --range 70-90 --delta 75   # Range of points
+nvcurve write --reset                    # Reset all to zero
+```
+
+> If you use LACT or similar tools, disable them before writing. Concurrent writes will overwrite each other.
+
+### Snapshots
+
+Snapshots are saved automatically before every write. You can also manage them manually:
+
+```bash
+nvcurve snapshot save
+nvcurve snapshot list
+nvcurve snapshot restore
+```
+
+Snapshots are stored in `/var/cache/nvcurve/snapshots`.
+
+### Profiles
+
+Profiles save a named set of curve offsets (plus optional memory offset and power limit settings). Profile commands work whether or not the server is running.
+
+```bash
+nvcurve profile save my_profile        # Save current curve state
+nvcurve profile apply my_profile       # Apply a saved profile
+nvcurve profile list                   # List all profiles
+nvcurve profile default my_profile     # Set as auto-load on startup
+nvcurve profile default --clear        # Clear auto-load setting
+```
+
+Profiles are stored as JSON files in `/etc/nvcurve/profiles`.
+
+### Diagnostics
+
+```bash
+nvcurve read --diag                     # Full NvAPI function probe + system info
+nvcurve inspect --point 80              # Raw ClockBoostTable fields
+nvcurve inspect --range 78-82           # Inspect a range of points
+nvcurve gpus                            # List detected GPUs
+```
+
+### Global Arguments
+
+The `--gpu N` flag can be placed before or after any subcommand to target a specific GPU in multi-GPU setups:
+
+```bash
+nvcurve --gpu 1 read
+nvcurve read --gpu 1
+nvcurve --gpu 1 profile default perf
+```
+
+## Systemd Service
+
+Install NVCurve as a systemd service for automatic profile loading on boot:
+
+### Install
+
+```bash
+nvcurve service install
+```
+
+With optional web server auto-start:
+
+```bash
+nvcurve service install --auto-serve --host 0.0.0.0 --port 8042
+```
+
+### Manage
+
+```bash
+nvcurve service start
+nvcurve service stop
+nvcurve service restart
+nvcurve service status
+nvcurve service uninstall
+```
+
+### Reconfigure
+
+```bash
+sudo nvcurve service configure --auto-serve
+sudo nvcurve service configure --no-auto-serve
+sudo nvcurve service configure --host 0.0.0.0 --port 8042
+```
+
+## Configuration Files
+
+| File | Purpose |
+|---|---|
+| `/etc/nvcurve/config.json` | Persistent config (host, port, auto-serve, default profiles) |
+| `/etc/nvcurve/profiles/*.json` | Saved profiles |
+| `/var/cache/nvcurve/snapshots/` | Auto-saved snapshots before writes |
+| `/run/nvcurve.json` | Runtime server info (host, port, PID) |
+| `/etc/systemd/system/nvcurve.service` | Systemd unit file |
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