# Terminal Route: DEEP SURVEY UNIT — RSU-7

## Machine fiction

RSU-7 is a fictional underwater research vessel command shell. The terminal boots on a fictionalised "Reef OS v2.4" and provides crew with real-time survey, maintenance, and navigation tools. The interface is keyboard-first, styled with muted teal-on-charcoal aesthetics and sonar-inspired visual elements. Exploration is rewarded with discovering hidden system logs, diagnostic outputs, and lore fragments.

## Interaction model

- Full keyboard navigation (Arrow Up/Down for history, Tab for completion, Ctrl+C to cancel)
- Click/tap on output lines focuses them; mobile uses larger tap targets
- Command grammar: `<verb> [noun] [--flag]`
- At least 12 meaningful commands with stateful responses
- Fake filesystem with a data partition (`/survey`, `/logs`, `/config`)
- Session-persisted history (localStorage, max 50 entries)
- Narrative anomaly layer: occasional ambient system events (pressure warnings, ping echoes, data artefacts)

## Commands

| Command | Description | State change |
|---|---|---|
| `help [cmd]` | Show general or command-specific help | No |
| `clear` | Clear terminal screen | Yes (buffer cleared) |
| `echo [text]` | Echo text to terminal | No |
| `history` | Show command history | No |
| `whoami` | Display current user and vessel info | No |
| `date` | Display current UTC date/time | No |
| `status` | Full system status (vessel, power, sensors, network) | No |
| `survey [--map]` | Run survey sweep; `--map` shows grid | No |
| `vent [open/close/status]` | Manage vent valves | Yes |
| `seal [engage/release/status]` | Manage seal mechanisms | Yes |
| `power [--cycle]` | Power subsystem report; `--cycle` triggers diagnostic | No |
| `map [--export]` | Generate bathymetric map; `--export` saves to /survey | Yes |
| `probe [sector]` | Run sonar probe on a sector | No |
| `log [--last N]` | Show system logs; `--last N` for tail | No |
| `diff [file1] [file2]` | Compare two log files | No |
| `cd [dir]` | Change directory (survey, logs, config, root) | Yes |
| `ls [dir]` | List directory contents | No |
| `cat [file]` | Display file contents | No |
| `ping [host]` | Ping a network host | No |
| `scan [--deep]` | Scan for anomalies; `--deep` is thorough | No |
| `unlock [code]` | Attempt to unlock classified data partition | Yes |

## Visual direction

- Background: #0d1117 (deep charcoal)
- Primary text: #4fd1c5 (muted teal)
- Accent/command: #81e6d9 (bright teal)
- Warning: #f6ad55 (amber)
- Error: #fc8181 (coral red)
- Font: `"Courier New", Courier, monospace` — authentic terminal feel
- Subtle scan-line overlay (CSS repeating-linear-gradient)
- Flicker animation on boot sequence
- CRT-style subtle glow on text-shadow

## Quality constraints

- No static transcript illusion — commands execute and respond in real time
- Mobile: minimum 48px tap targets, no loss of fiction
- All file operations are in-memory simulation
- Error messages are specific and helpful (not just "command not found")
- Narrative events fire randomly (1 in 20 commands) to reward continued exploration

## Output contract

- `PROMPT.md` — this file
- `index.html` — complete single-file terminal artifact
- `artifact.json` — metadata (slug: terminal, order: 50, skill: oneshot-terminal)