feat: pos media yt — unified YouTube tools + subtitles (POS--9)

feat: install.sh version gate — --force + per-commit 0.0cN
Architect-approved (C): install.sh now skips+aborts (exit 0) when the installed version equals the current git-derived version, with a --force flag to re-install. Version scheme 0.0cN (N = git commit count) bumps by construction on every commit. - install_version(): derives 0.0c$count via git rev-list; empty when .git absent (gate skipped); INSTALL_VERSION_OVERRIDE presence-check seam for tests (empty override simulates no-git deterministically) - Gate after arg parse, before phases; numeric comparison (strip 0.0c, -eq); messages: 'Already installed (X). Use --force to re-install.' and '(dry-run) Would skip install: already at version X', both exit 0 - flag_set installed_version after 'Bootstrap complete' banner (not in dry-run, even under --force, never on phase failure) - Docs: SCRIPTS.md flag table + gate description, AGENT_Context line count 248->301 + flags + flow diagram, README --force row, tests/README row, AGENT_TODO Done entry Verified: new tests/t-install-version.sh 21 checks (9 contracted cases, real install.sh + hermetic env seams); suite 20 files / 461 checks / 0 fail / 0 skip; make gen byte-idempotent; make check OK; make lint 0 FAIL, 0 WARN; bash -n clean; git diff --check clean; Reviewer APPROVE_WITH_NOTES with 3 mutation disproofs (8/21, 9/21, 4/21 fail)
2026-09-09 07:04:22 -04:00 · 2026-09-08 10:17:31 -04:00 · 2026-09-07 13:32:42 -04:00
28 changed files with 1478 additions and 501 deletions
@@ -42,6 +42,13 @@ summary (newest last).

 ## Done

+- **2026-09-09** — Unified YouTube tools into `pos media yt` + new `subtitles` (Architect POS--9). New `bin/pos-media-yt` dispatcher (mp3/mp4/grab/ytsync/subtitles) + `bin/pos-media-yt-{mp3,mp4,grab,subtitles,ytsync}`; the ytsync file is a forwarder to the existing `pos media ytsync`; legacy `bin/pos-media-{mp3,mp4,grab}` became thin forwarders to the `yt` forms. New `lib/yt-lib.sh` (deps/URL-validation/echo/classify helpers; `classify_url` migrated from grab, `yt_validate_url` is a return-1 checker — never exits, so callers can prefix errors). `bin/pos` INTERACTIVE_CMDS += `media-yt-mp4` (interactive format pick reads stdin). `pos-media-yt-subtitles` extracts captions via `--write-subs --write-auto-subs --sub-langs best`, `--lang en,ar` (one `--sub-langs` arg), `srt|vtt|txt` (txt = srt→txt conversion stripping timestamps/HTML), `--auto-only`, `--list-subs` probe, `--output`, no-ffmpeg dep (yt-dlp only; dry-run skips deps entirely). Docs: DOC/POS.md media section rewritten (yt group + forwarder rows), DOC/howto/media.md `yt` commands + subtitles section, AGENT_Context hand-maintained `lib/yt-lib.sh` row, tests/README row. New `tests/t-pos-media-yt.sh` (72 checks: dispatcher/forwarder resolution, full `pos media mp3` dispatch chain, yt-lib helpers, per-tool flags/dry-run/`YT_OUT_DIR` seam/`GRAB_DEFAULT` config, 3 mandated negative controls — unsafe-URL no-expansion, `--lang en,ar` single arg, txt timestamp-stripping, unavailable-subs detection). `tests/t-config-precedence.sh` Part D config-consumer list updated `pos-media-grab` → `pos-media-yt-grab`. Verified: `bash -n` all; `make gen` ×2 byte-idempotent; `make check` OK; `make lint` 0 FAIL / 0 WARN; `make test` 21 files / 533 checks / 0 fail / 0 skip; `git diff --check` clean; smokes — `pos media yt --help`, `yt mp3/mp4/subtitles --help`, `yt ytsync --help` (reaches `pos media ytsync`), `pos media mp3 --help` forwarder, `pos tree` shows the `yt` subtree (with repo-first PATH; system `/usr/local/bin` has a stale pre-POS--9 install that shadows it otherwise).
+
+- **2026-09-08** — `install.sh` version gate (Architect→Builder): skip+abort when installed version == current version, `--force` to bypass, version scheme `0.0c<git commit count>` (auto-bumps per commit). `install_version()` derives `0.0c$(git rev-list --count HEAD)`; empty when `.git` absent → gate skipped (silently); `INSTALL_VERSION_OVERRIDE` env var (presence-check) = test seam. Gate after arg-parse, before phases, numeric comparison (strip `0.0c`, `-eq`); `log "Already installed ($CURRENT_VERSION). Use --force to re-install."` / `--dry-run` → `(dry-run) Would skip install: already at version $CURRENT_VERSION`, both exit 0. `FORCE=0` init, `--force` parse + usage. `flag_set installed_version "$CURRENT_VERSION"` after "Bootstrap complete" banner (only when DRY_RUN≠1 and version non-empty; even under --force). New `tests/t-install-version.sh` (21 checks / 9 cases). Docs: README/SCRIPTS/AGENT_Context (flags, flow, line count 248→301, tests/README row). Verified: `bash -n` clean; `make gen` idempotent; `make check` OK; `make lint` 0 FAIL / 0 WARN; `make test` suite green.
+
+
+- **2026-09-07** — `pos ai` API-key contract mismatch fixed (Architect→Builder→Reviewer; docs/history evidence): docs claimed `AI_API_KEY` was the required primary key, but `resolve_key()` read only provider-specific keys (`7ae2e77` had removed shared-key priority to fix cross-provider leakage; docs never updated). Decision C: provider key stays primary (leakage guard intact), legacy `AI_API_KEY` honored as backward-compat fallback when the provider's own key is empty; `cmd_providers()` "configured" mirrors it; `require_key()` messages byte-stable; `AI_API_KEY` NOT re-added to `# POS_CONFIG:`/`# PROVIDER_CONFIG:` registry. Docs reworded (POS.md rows 91/96/98 + precedence, howto/ai.md first-run hints, HOWTO.md, AGENT_Context 2 prose spots, config/ai.env comment). New regression `tests/t-ai-key-resolution.sh` (24 checks / 10 cases: gemini+openrouter via provider key only, via AI_API_KEY only, both→provider wins, env-wins, llamacpp no-key, missing-key message, providers configured status). Verified: suite 19 files / 440 checks / 0 fail / 0 skip; `make gen` byte-idempotent; `make check` OK; `make lint` 0 FAIL, 0 WARN; Reviewer APPROVE_WITH_NOTES with mutation-based disproof (inverted precedence → C3/C6 fail).
+
 - **2026-09-07** — opencode project skill: created `.opencode/skills/linux-post-install/SKILL.md` (repo had no `.opencode/`). Skill encodes the repo's operational playbook for agents: repo shape, `pos` tool model (`# POS:` header system, exec-bit, deps-guard-before-help, INTERACTIVE_CMDS, determinism), doc authority order (MAINTENANCE Phase 0: templates → DEV.md → AGENTS.md → code), Definition of Done gates (`make gen` ×2 idempotent → `make check` → `make lint` 0/0 → `make test` 18 files/416 checks), test conventions (hard-skip contract, negative controls), and repo commands (ci-status, gitea API, pos tree/config). Frontmatter validated (name matches folder, description with trigger keywords); auto-discovered at `.opencode/skills/` — no opencode.json change needed; restart opencode to load.

 - **2026-09-06** — Repo cleanup: removed 114 temp/process files (AgentsReport/ 86 + reportAgents/ 28 agent reports), stale task/plan/audit docs (tmp_request.md, FINAL_SUMMARY.md, IMPLEMENTATION_PLAN.md, AUDIT.md, AUDIT_TABLE.md, registry-design doc), stray `To`/`.n`/`reports/` artifacts; gitignored AgentsReport/ so agent process reports stay local-only. DOC/, tools-docs/ytsync.md, AGENT_TODO.md, bin/lib/apps/tests/config/scripts etc. kept untouched.
@@ -10,19 +10,19 @@

 <!-- GEN:START docmap -->
 | ## 1. Project Overview | 28–43 |
-| ## 2. Directory Structure | 44–210 |
-| ## 3. Installation Flow | 211–264 |
-| ## 4. The `pos` CLI System | 265–346 |
-| ## 5. Shared Library — `lib/common.sh` | 347–378 |
-| ## 6. Docker Compose / ScaleTail | 379–421 |
-| ## 7. Optional Apps (`apps/`) | 422–451 |
-| ## 8. Entertainment Module | 452–465 |
-| ## 9. Systemd Services | 466–477 |
-| ## 10. Configuration Files | 478–504 |
-| ## 11. Coding Conventions | 505–537 |
-| ## 12. Development Workflow | 538–590 |
-| ## 13. Key File Quick Reference | 591–666 |
-| ## 14. Common Tasks for Agents | 667–700 |
+| ## 2. Directory Structure | 44–216 |
+| ## 3. Installation Flow | 217–275 |
+| ## 4. The `pos` CLI System | 276–363 |
+| ## 5. Shared Library — `lib/common.sh` | 364–395 |
+| ## 6. Docker Compose / ScaleTail | 396–438 |
+| ## 7. Optional Apps (`apps/`) | 439–468 |
+| ## 8. Entertainment Module | 469–482 |
+| ## 9. Systemd Services | 483–494 |
+| ## 10. Configuration Files | 495–521 |
+| ## 11. Coding Conventions | 522–554 |
+| ## 12. Development Workflow | 555–607 |
+| ## 13. Key File Quick Reference | 608–690 |
+| ## 14. Common Tasks for Agents | 691–724 |
 <!-- GEN:END docmap -->

 ## 1. Project Overview
@@ -90,7 +90,13 @@ Linux_post_install/
 │   ├── pos-media-mp4                       # Download video as MP4 (smart/interactive format select)
 │   ├── pos-media-sync                      # Incremental Music → USB sync (mp3/mp4, add/update only)
 │   │   [deps: lsblk jq]
+│   ├── pos-media-yt-grab                   # Auto-download URL as audio or video (classify + route)
+│   ├── pos-media-yt-mp3                    # Download audio as MP3 (yt-dlp)
+│   ├── pos-media-yt-mp4                    # Download video as MP4 (smart/interactive format select)
+│   ├── pos-media-yt-subtitles              # Extract subtitles/captions from a URL (yt-dlp)
+│   ├── pos-media-yt-ytsync                 # Incrementally sync YouTube channels/playlists into ~/Videos
 │   ├── pos-media-ytsync                    # Incrementally sync YouTube channels/playlists into ~/Videos
+│   ├── pos-media-yt                        # YouTube download tools (mp3/mp4/grab/ytsync/subtitles)
 │   ├── pos-network-checkport               # Check TCP/UDP port reachability (nmap, or bash/nc fallback) + local interface view
 │   ├── pos-network-download                # aria2 RPC daemon + queue control (add/torrent/metalink, watch, limits)
 │   │   [deps: aria2c jq curl]
@@ -211,7 +217,11 @@ Linux_post_install/
 ## 3. Installation Flow

 ```
-User runs: ./install.sh [--apps|--full|--feature|--dry-run|--skip <phase>|--steps <spec>]
+User runs: ./install.sh [--apps|--full|--feature|--dry-run|--force|--skip <phase>|--steps <spec>]
+│
+├─ Version gate: compares installed version (flag) vs current (0.0c<commit count>)
+│   └─ match + no --force → "Already installed. Use --force to re-install." / exit 0
+│       (--dry-run variant prints "Would skip install"); no git or no flag → skip gate
 │
 ├─ Phase 1: preinstall.sh        (requires root)
 │   └─ apt update + installs 25+ packages + yt-dlp + fail2ban
@@ -249,6 +259,7 @@ User runs: ./install.sh [--apps|--full|--feature|--dry-run|--skip <phase>|--step
 | `--full` | Core install + all apps (non-interactive) |
 | `--feature` | Install `features/` scripts to `/usr/local/bin/` (asks before overwriting), set their flags |
 | `--dry-run` | Preview without executing |
+| `--force` | Re-install even if the version matches |
 | `--skip <phase>` | Skip a phase (repeatable): `preinstall`, `scripts`, `postinstall`, `scalepoint`, `apps` |
 | `--steps <spec>` | Run only specific phases. Format: `1,3,4` or `1-3` |
 | `--no-color` | Disable colored output |
@@ -306,7 +317,13 @@ All non-interactive `pos` commands log output to `~/.local/share/linux_post_inst
 | media | mp3 | `pos-media-mp3` | Download audio as MP3 (yt-dlp) |  |  |
 | media | mp4 | `pos-media-mp4` | Download video as MP4 (smart/interactive format select) |  |  |
 | media | sync | `pos-media-sync` | Incremental Music → USB sync (mp3/mp4, add/update only) | lsblk jq | pos media sync --mp3 → Sync only MP3 files to USB · pos media sync --mp4 --dry-run → Preview MP4 sync without copying |
+| media | yt-grab | `pos-media-yt-grab` | Auto-download URL as audio or video (classify + route) |  |  |
+| media | yt-mp3 | `pos-media-yt-mp3` | Download audio as MP3 (yt-dlp) |  |  |
+| media | yt-mp4 | `pos-media-yt-mp4` | Download video as MP4 (smart/interactive format select) |  |  |
+| media | yt-subtitles | `pos-media-yt-subtitles` | Extract subtitles/captions from a URL (yt-dlp) |  |  |
+| media | yt-ytsync | `pos-media-yt-ytsync` | Incrementally sync YouTube channels/playlists into ~/Videos |  |  |
 | media | ytsync | `pos-media-ytsync` | Incrementally sync YouTube channels/playlists into ~/Videos |  |  |
+| media | yt | `pos-media-yt` | YouTube download tools (mp3/mp4/grab/ytsync/subtitles) |  |  |
 | network | checkport | `pos-network-checkport` | Check TCP/UDP port reachability (nmap, or bash/nc fallback) + local interface view |  |  |
 | network | download | `pos-network-download` | aria2 RPC daemon + queue control (add/torrent/metalink, watch, limits) | aria2c jq curl | pos network download add https://example.com/file.zip → Enqueue an HTTP download (auto-starts daemon) · pos network download status → Daemon health + global transfer stats · pos network download watch → Live progress view |
 | network | hotspot | `pos-network-hotspot` | Wi-Fi hotspot via create_ap + wihotspot-gui |  |  |
@@ -371,7 +388,7 @@ source "$(dirname "$0")/../lib/common.sh"

 **Scripts that do NOT source common.sh** (self-contained):
 <!-- GEN:START selfcontained -->
-`pos`, `pos-ai-gemini`, `pos-ai-llamacpp`, `pos-ai-openrouter`, `pos-communication-matrix-sender`, `pos-communication-telegram-listener`, `pos-communication-telegram-sender`, `pos-network-checkport`, `pos-network-hotspot`, `pos-network-ip`, `pos-network-scan`, `pos-ssh-load-keys`, `pos-system-firewall`.
+`pos`, `pos-ai-gemini`, `pos-ai-llamacpp`, `pos-ai-openrouter`, `pos-communication-matrix-sender`, `pos-communication-telegram-listener`, `pos-communication-telegram-sender`, `pos-media-grab`, `pos-media-mp3`, `pos-media-mp4`, `pos-media-yt-ytsync`, `pos-network-checkport`, `pos-network-hotspot`, `pos-network-ip`, `pos-network-scan`, `pos-ssh-load-keys`, `pos-system-firewall`.
 <!-- GEN:END selfcontained -->

 ---
@@ -488,7 +505,7 @@ All `.service` files in `systemd/` are automatically copied to `/etc/systemd/sys
 - `~/.config/linux_post_install/entertainment.env` — entertainment plugin defaults: weather location + `ENABLED` auto-trigger list (`plugin, interval` pairs scheduled via `pos entertainment enable/disable`, systemd user timers); auto-installed from `config/entertainment.env` by `postinstall.sh` (no clobber, template printed)
 - `~/.config/linux_post_install/system.env` — shared "system" tool settings (loaded by `pos system health` / `pos system backup` via `load_system_env()` in `lib/common.sh`; env already exported wins over the file); template `config/system.env`
 - `~/.config/linux_post_install/notify.env` — alerting platform selection (`NOTIFY_PLATFORM=telegram,matrix`, comma-separated = fan out); read by `lib/notify.sh`; template `config/notify.env`
- `~/.config/linux_post_install/ai.env` — AI provider config (`AI_PROVIDER`, `AI_API_KEY` secret, `AI_MODEL`, `AI_SYSTEM_PROMPT`, `AI_MAX_TOKENS`, `AI_SESSION_TURNS`, plus legacy fallbacks `AI_GEMINI_API_KEY`, `AI_GEMINI_MODEL`, `OPENROUTER_API_KEY`, `OPENROUTER_MODEL`); read by `pos ai`; template `config/ai.env`, auto-installed by postinstall, edit with `pos config ai`
+- `~/.config/linux_post_install/ai.env` — AI provider config (`AI_PROVIDER`, `AI_MODEL`, `AI_SYSTEM_PROMPT`, `AI_MAX_TOKENS`, `AI_SESSION_TURNS`, provider keys `AI_GEMINI_API_KEY`/`OPENROUTER_API_KEY` (secrets), legacy shared fallback `AI_API_KEY` accepted when the provider's key is unset, plus model fallbacks `AI_GEMINI_MODEL`, `OPENROUTER_MODEL`); read by `pos ai`; template `config/ai.env`, auto-installed by postinstall, edit with `pos config ai`
 - `~/.bashrc` — Modified by postinstall (PATH, bash completion)

 ### Feature Flags
@@ -592,7 +609,7 @@ Use conventional prefixes: `feat:`, `fix:`, `docs:`, `refactor:`, `chore:`

 | File | Lines | Purpose |
 |------|-------|---------|
-| `install.sh` | 248 | Main orchestrator — 4 phases with CLI flags, `--feature`, prebuilt arch bins |
+| `install.sh` | 301 | Main orchestrator — 4 phases with CLI flags, `--feature`, `--force`, version gate, prebuilt arch bins |
 | `preinstall.sh` | 76 | System packages + hotspot deps + yt-dlp + fail2ban |
 | `postinstall.sh` | 168 | fail2ban config, PATH, bash completion, systemd (flag-gated) |
 | `lib/common.sh` | 151 | Shared library (log/warn/err/run/spawn, dry-run aware, `load_system_env`, CONFIG_DIR) |
@@ -606,6 +623,7 @@ Use conventional prefixes: `feat:`, `fix:`, `docs:`, `refactor:`, `chore:`
 | `lib/share-lib.sh` | 318 | Domain layer for the share suite (usbsrv/smbclient record parsers, folder+mountpoint candidates, remote listings, service/firewall advisories; EOF-safe) + compat shims to `lib/menu-lib.sh` — used by all five `pos share *` tools |
 | `lib/menu-lib.sh` | 362 | Category-neutral interactive menu primitives (`menu_guard` tty guard, `menu_run` looping boxed menu, `menu_pick` type-to-filter picker, `menu_ask_value` prompt-with-default via raw-mode bracketed-paste-safe `menu_read_value`; stderr render, fail-closed on non-tty/EOF) — sourced by `share-lib.sh`, open to any category |
 | `lib/registry.sh` | 199 | Shared query API for POS tool metadata headers (`# POS_*:`) — `reg_scan`/`reg_list`/`reg_lookup`/`reg_each`/config scope helpers; used by `pos-tree` and `gen-docs.sh` |
+| `lib/yt-lib.sh` | 50 | Shared YouTube helpers for `pos media yt *` (`yt_check_deps`, `yt_validate_url`, `yt_echo_cmd`, `classify_url`) — sourced by `yt-mp3`/`yt-mp4`/`yt-grab`/`yt-subtitles` |
 | `bin/flag-reader` | 58 | Inspect flags (list/status/`--raw`) |
 | `bin/flag-set` | 21 | Set a flag (optionally with a value) |
 | `bin/flag-clear` | 21 | Unset a flag |
@@ -634,11 +652,17 @@ Use conventional prefixes: `feat:`, `fix:`, `docs:`, `refactor:`, `chore:`
 | `bin/pos-entertainment-enable` | 49 | Enable an auto-trigger for a plugin on a schedule |
 | `bin/pos-entertainment-send` | 95 | Run a public-API plugin and send its output via the configured notify platforms |
 | `bin/pos-entertainment-status` | 62 | Show enabled plugins and scheduler state |
-| `bin/pos-media-grab` | 219 | Auto-download URL as audio or video (classify + route) |
-| `bin/pos-media-mp3` | 86 | Download audio as MP3 (yt-dlp) |
-| `bin/pos-media-mp4` | 132 | Download video as MP4 (smart/interactive format select) |
+| `bin/pos-media-grab` | 5 | Auto-download URL as audio or video (classify + route) |
+| `bin/pos-media-mp3` | 5 | Download audio as MP3 (yt-dlp) |
+| `bin/pos-media-mp4` | 5 | Download video as MP4 (smart/interactive format select) |
 | `bin/pos-media-sync` | 219 | Incremental Music → USB sync (mp3/mp4, add/update only) |
+| `bin/pos-media-yt-grab` | 208 | Auto-download URL as audio or video (classify + route) |
+| `bin/pos-media-yt-mp3` | 86 | Download audio as MP3 (yt-dlp) |
+| `bin/pos-media-yt-mp4` | 132 | Download video as MP4 (smart/interactive format select) |
+| `bin/pos-media-yt-subtitles` | 169 | Extract subtitles/captions from a URL (yt-dlp) |
+| `bin/pos-media-yt-ytsync` | 5 | Incrementally sync YouTube channels/playlists into ~/Videos |
 | `bin/pos-media-ytsync` | 1213 | Incrementally sync YouTube channels/playlists into ~/Videos |
+| `bin/pos-media-yt` | 33 | YouTube download tools (mp3/mp4/grab/ytsync/subtitles) |
 | `bin/pos-network-checkport` | 498 | Check TCP/UDP port reachability (nmap, or bash/nc fallback) + local interface view |
 | `bin/pos-network-download` | 1113 | aria2 RPC daemon + queue control (add/torrent/metalink, watch, limits) |
 | `bin/pos-network-hotspot` | 93 | Wi-Fi hotspot via create_ap + wihotspot-gui |
@@ -655,10 +679,10 @@ Use conventional prefixes: `feat:`, `fix:`, `docs:`, `refactor:`, `chore:`
 | `bin/pos-system-health` | 209 | Host health dashboard (disk, RAM, services, backup age, fail2ban, docker); exit 1 if any FAIL |
 | `bin/pos-system-schedule` | 151 | Scheduled jobs: run a command on a timer; notify on threshold/change/error/always or silently |
 | `bin/pos-system-uninstall` | 517 | Remove pos toolkit binaries, services, shell integration, config, and data |
-| `bin/pos-ai` | 709 | AI assistant: ask, chat, sessions, capture, models, providers |
+| `bin/pos-ai` | 714 | AI assistant: ask, chat, sessions, capture, models, providers |
 | `bin/pos-config` | 80 | Interactive editor for the tools' runtime config (reads # POS_CONFIG: registry) |
 | `bin/pos-tree` | 118 | Show the pos CLI command tree: categories, commands, and subcommands |
-| `completions/pos.bash` | 314 | Dynamic bash completion |
+| `completions/pos.bash` | 316 | Dynamic bash completion |
 <!-- GEN:END filetable -->
 | `apps/install.sh` | 171 | App install/uninstall picker/orchestrator |

@@ -692,7 +716,7 @@ Use conventional prefixes: `feat:`, `fix:`, `docs:`, `refactor:`, `chore:`
 | Modify Music→USB sync logic | Edit `bin/pos-media-sync` / shared USB layer `lib/usb-lib.sh` (seams `MEDIA_SYNC_SOURCE`/`MEDIA_SYNC_DEST`/`USB_MOUNT_BASE`/`USB_BYID` in `~/.config/linux_post_install/system.env`) |
 | Modify YouTube channel sync logic | Edit `bin/pos-media-ytsync` (state in `~/.local/share/linux_post_install/ytsync`; config scope `ytsync` via `pos config ytsync`; research notes `tools-docs/ytsync.md`) |
 | Modify the scheduler / scheduled jobs | Edit `bin/pos-system-schedule` / `lib/scheduler-lib.sh` (jobs in `~/.config/linux_post_install/schedule.d/`) |
-| Modify AI logic | Edit `bin/pos-ai` (main tool) + `lib/ai-providers/*.sh` (provider adapters); config scope `ai` via `pos config ai`; `AI_API_KEY`/`AI_MODEL`/`AI_PROVIDER` in `~/.config/linux_post_install/ai.env` |
+| Modify AI logic | Edit `bin/pos-ai` (main tool) + `lib/ai-providers/*.sh` (provider adapters); config scope `ai` via `pos config ai`; `AI_PROVIDER`, `AI_MODEL`, per-provider `AI_GEMINI_API_KEY`/`OPENROUTER_API_KEY` (legacy shared `AI_API_KEY` accepted as fallback) in `~/.config/linux_post_install/ai.env` |
 | Modify UFW/firewall logic | Edit `bin/pos-system-firewall` |
 | Modify pos logging | Edit log setup in `bin/pos` |
 | Modify install phases/flags | Edit arg parsing in `install.sh` |
@@ -42,7 +42,7 @@ templates (without overwriting an existing file):
 | `system.env` | `pos system health`, `pos system backup` | `BACKUP_SERVICE_ROOTS`, `HEALTH_BACKUP_MAX_AGE_DAYS` |
 | `compose.env` | `pos docker compose` | `TS_AUTHKEY`, `TZ`, `DNS_SERVER`, `SERVICES_BASE` |
 | `entertainment.env` | `pos entertainment *` | plugin keys (`WEATHER_LAT`…), `ENABLED` |
-| `ai.env` | `pos ai` | `AI_PROVIDER`, `AI_API_KEY`, `AI_MODEL`, `AI_SYSTEM_PROMPT`, `AI_MAX_TOKENS`, `AI_SESSION_TURNS`, `AI_GEMINI_API_KEY`, `AI_GEMINI_MODEL`, `OPENROUTER_API_KEY`, `OPENROUTER_MODEL` |
+| `ai.env` | `pos ai` | `AI_PROVIDER`, `AI_MODEL`, `AI_SYSTEM_PROMPT`, `AI_MAX_TOKENS`, `AI_SESSION_TURNS`, provider keys `AI_GEMINI_API_KEY` / `OPENROUTER_API_KEY` (+ legacy `AI_API_KEY` fallback) |
 | `schedule.d/` | `pos system schedule` | one `<name>.env` per job: `INTERVAL`, `NOTIFY`, `MSG`, `RULE`, `COMMAND` |

 ```bash
@@ -88,17 +88,17 @@ Backward compatibility: `pos ai gemini`, `pos ai openrouter`, and `pos ai llamac
 | Key | Required | Default | Purpose |
 |-----|----------|---------|---------|
 | `AI_PROVIDER` | no | `gemini` | Active provider (gemini\|openrouter\|llamacpp) |
-| `AI_API_KEY` | yes | — | API key for the active provider (secret — masked in `pos config ai`) |
+| `AI_API_KEY` | no (legacy fallback) | — | Legacy shared API key, used when the active provider's key is empty; not part of the `pos config ai` prompt (set via env or hand-edit); secret |
 | `AI_MODEL` | no | per provider | Model id used by `ask`/`chat`/`models` |
 | `AI_SYSTEM_PROMPT` | no | built-in terse prompt | Custom system prompt (overrides built-in; empty to reset) |
 | `AI_MAX_TOKENS` | no | `2048` | Max output tokens per request (OpenRouter/Gemini cost cap) |
 | `AI_SESSION_TURNS` | no | `40` | Session message cap — 2 per exchange; 10 = last 5 exchanges |
-| `AI_GEMINI_API_KEY` | fallback | — | Legacy: Gemini API key (used when `AI_API_KEY` is empty) |
+| `AI_GEMINI_API_KEY` | yes (gemini) | — | Gemini API key (the active key when provider is gemini; secret — masked in `pos config ai`) |
 | `AI_GEMINI_MODEL` | fallback | `gemini-2.5-flash` | Legacy: Gemini model id (used when `AI_MODEL` is empty) |
-| `OPENROUTER_API_KEY` | fallback | — | Legacy: OpenRouter API key (used when `AI_API_KEY` is empty) |
+| `OPENROUTER_API_KEY` | yes (openrouter) | — | OpenRouter API key (the active key when provider is openrouter; secret — masked in `pos config ai`) |
 | `OPENROUTER_MODEL` | fallback | `openrouter/auto` | Legacy: OpenRouter model id (used when `AI_MODEL` is empty) |

-Model precedence: `--model` flag > `AI_MODEL` env > provider-specific fallback (`AI_GEMINI_MODEL`/`OPENROUTER_MODEL`) > provider default. API key precedence: `AI_API_KEY` env > provider-specific fallback (`AI_GEMINI_API_KEY`/`OPENROUTER_API_KEY`) > error. `postinstall.sh` copies the repo's `config/ai.env` template to `~/.config/linux_post_install/ai.env` on install (no clobber). Dependencies: `curl` + `jq` (both in `preinstall.sh` PACKAGES). Sessions are stored in OpenAI `messages` format universally; old Gemini-format sessions (`contents[]`) are auto-migrated on load.
+Model precedence: `--model` flag > `AI_MODEL` env > provider-specific fallback (`AI_GEMINI_MODEL`/`OPENROUTER_MODEL`) > provider default. API key precedence: `<provider>_API_KEY` (`AI_GEMINI_API_KEY` for gemini / `OPENROUTER_API_KEY` for openrouter) > legacy `AI_API_KEY` fallback > error. `AI_API_KEY` is an internal adapter shim and a backward-compat input — it is not offered by `pos config ai`. `postinstall.sh` copies the repo's `config/ai.env` template to `~/.config/linux_post_install/ai.env` on install (no clobber). Dependencies: `curl` + `jq` (both in `preinstall.sh` PACKAGES). Sessions are stored in OpenAI `messages` format universally; old Gemini-format sessions (`contents[]`) are auto-migrated on load.

 **Messaging bridges:** the Telegram and Matrix listeners forward non-command messages starting with `ai ` (case-insensitive) to `pos ai ask` and reply with the model's answer — see [communication → listener](#communication). The Telegram bridge uses one session per chat (`telegram-<chat id>`), the Matrix bridge one per room (`matrix-<room>`).

@@ -263,9 +263,15 @@ The standalone `vbox` command still works and forwards to `pos docker vbox` (see

 | Command | File | Purpose | Configuration |
 |---------|------|---------|---------------|
-| `pos media mp3 <url>` | `bin/pos-media-mp3` | Download audio as MP3 via yt-dlp, with thumbnail + metadata | Output to `~/Music/%(title)s.%(ext)s`, `--audio-quality 0` |
-| `pos media mp4 <url>` | `bin/pos-media-mp4` | Download video via yt-dlp with **interactive format selection** | Lists formats (`yt-dlp -F`), asks for a format ID, saves to `~/Videos/` |
-| `pos media grab <url>` | `bin/pos-media-grab` | Auto-download a URL as audio or video (classify + route to mp3/mp4) | Domain-based classification (YouTube Music/SoundCloud/Bandcamp → audio; YouTube/Vimeo/Twitch → video); `--audio`/`--video` force the mode; `--best` default for video (non-interactive); prints a clean summary (🎵/🎬 title, path, size). Config: `GRAB_DEFAULT` (`pos config grab`, default `video`) for unknown domains |
+| `pos media yt` | `bin/pos-media-yt` | YouTube download tools dispatcher (mp3/mp4/grab/ytsync/subtitles); bare invocation prints help listing subcommands | Subcommands resolved via `bin/pos-media-yt-<sub>` files |
+| `pos media yt mp3 <url>` | `bin/pos-media-yt-mp3` | Download audio as MP3 via yt-dlp, with thumbnail + metadata | Output to `~/Music/%(title)s.%(ext)s`, `--audio-quality 0`; `--by-artist` organizes as `<dir>/<artist>/<title>.mp3`. Env seam: `YT_OUT_DIR` overrides the default output dir |
+| `pos media yt mp4 <url>` | `bin/pos-media-yt-mp4` | Download video via yt-dlp with **interactive format selection** | Lists formats (`yt-dlp -F`), asks for a format ID, saves to `~/Videos/`; `-f/--best/--worst` skip the prompt. Env seam: `YT_OUT_DIR` overrides the default output dir. Reads stdin (interactive format pick) → in `INTERACTIVE_CMDS` |
+| `pos media yt grab <url>` | `bin/pos-media-yt-grab` | Auto-download a URL as audio or video (classify + route to yt-mp3/yt-mp4) | Domain-based classification (YouTube Music/SoundCloud/Bandcamp → audio; YouTube/Vimeo/Twitch → video); `--audio`/`--video` force the mode; `--best` default for video (non-interactive); prints a clean summary (🎵/🎬 title, path, size). Config: `GRAB_DEFAULT` (`pos config grab`, default `video`) for unknown domains |
+| `pos media yt ytsync [add\|sync\|list\|remove]` | `bin/pos-media-yt-ytsync` | Thin forwarder → `pos media ytsync` (incremental YouTube channel/playlist sync into `~/Videos`) | See `bin/pos-media-ytsync` below |
+| `pos media yt subtitles <url>` | `bin/pos-media-yt-subtitles` | Extract subtitles/captions from a URL (yt-dlp) | Default `--write-subs --write-auto-subs --sub-langs best`; `--lang en,ar` (comma = single `--sub-langs` arg); `--format srt` (default) / `vtt` / `txt` (srt→txt post-conversion); `--auto-only` drops manual subs; `--list-subs` probe; output to current dir (`-o ./%(title)s.%(sub_lang)s.%(ext)s`), `--output <dir>` overrides. Non-interactive; needs only yt-dlp (no ffmpeg) |
+| `pos media mp3 <url>` | `bin/pos-media-mp3` | **Forwarder** → `pos media yt mp3` (backward-compat alias) | Legacy spelling still works |
+| `pos media mp4 <url>` | `bin/pos-media-mp4` | **Forwarder** → `pos media yt mp4` (backward-compat alias) | Legacy spelling still works |
+| `pos media grab <url>` | `bin/pos-media-grab` | **Forwarder** → `pos media yt grab` (backward-compat alias) | Legacy spelling still works |
 | `pos media sync [--mp3\|--mp4]` | `bin/pos-media-sync` | Incremental Music → USB sync (add/update only — never deletes) | Copies mp3/mp4 from `$HOME/Music` (or `--source <dir>`) into `<usb>/Music/`, preserving the tree; missing or changed (size/mtime) files are copied, identical ones skipped. Same USB detection as `pos system backup` (lsblk TRAN + lsusb/by-id, mount offer for unmounted sticks, multi-stick picker). `--mp3`/`--mp4` filter by extension, neither = both; `--dry-run` previews. Config: `MEDIA_SYNC_SOURCE`, `MEDIA_SYNC_DEST`, shared `USB_MOUNT_BASE`/`USB_BYID` from `~/.config/linux_post_install/system.env`. Result notified via `lib/notify.sh`. Bare invocation on a terminal (or the `menu` subcommand) opens an interactive menu wrapping these actions (sync now mp3+mp4, dry-run preview, mp3-only, mp4-only, change source folder); flags stay scriptable |
 | `pos media ytsync [add\|sync\|list\|remove]` | `bin/pos-media-ytsync` | Incremental YouTube channel/playlist sync — first run asks for a URL (bare invocation = interactive menu; empty state goes straight to the prompt), repeat runs fetch only new videos | One yt-dlp call per new video (`bestvideo*+bestaudio/best` → MP4, metadata/chapters/thumbnail embedded, `--no-overwrites`, `--windows-filenames --trim-filenames 120`); per-source `--download-archive` (`~/.local/share/linux_post_install/ytsync/archive/<slug>.txt`) makes runs crash-safe and idempotent; registry tracks slug/type/url/subdir. Verbs never prompt (scheduler/timer safe); non-tty interactive entry prints a guard line and exits 0. `--dry-run` probes + plans with zero writes. Notify digest only when new>0 or failed>0 via `lib/notify.sh`. Config: `YTSYNC_VIDEOS_DIR`, `YTSYNC_EXTRA_ARGS` via `pos config ytsync`; automate with `pos system schedule` (`COMMAND=pos media ytsync sync`, `NOTIFY=never`) |

@@ -34,7 +34,8 @@ Everything that runs during the bootstrap install: `install.sh`, `preinstall.sh`
 1. **Pre-parse `--no-color`** before anything else, so colors are disabled early (`TERM=dumb` is exported).
 2. Source `lib/common.sh` (logging, `run`, `spawn`, …) and `lib/flags.sh` (feature flags).
 3. Parse CLI options.
-4. For each phase, `should_run <num> <name>` decides whether to run it:
+4. **Version gate:** derive the current version (`0.0c<git commit count>` via `install_version()`; empty when `.git` is absent). If the installed version (stored as the `installed_version` flag) matches and `--force` is not given, skip the install — with `--dry-run` it prints `(dry-run) Would skip install: already at version <v>`, otherwise `Already installed (<v>). Use --force to re-install.` and exits 0. When no `installed_version` flag exists or the current version cannot be determined (no `.git`), the gate is skipped.
+5. For each phase, `should_run <num> <name>` decides whether to run it:
   - `--skip <phase>` removes a phase (takes precedence).
   - `--steps <spec>` restricts the run to the listed phases only (`1,3,4` or `1-3`).
   - Phase map: `1=preinstall`, `2=scripts`, `3=postinstall`, `4=scalepoint` (+ `apps` handled separately).
@@ -63,6 +64,7 @@ No config file — everything is command-line:
 | `--full` | Core install + every app (non-interactive) |
 | `--feature` | Install `features/` scripts to `/usr/local/bin/` (prompts on overwrite), sets their flags |
 | `--dry-run` | Log every action instead of executing. **Note:** applies to `install.sh` itself; `postinstall.sh` runs as a subprocess and does not inherit `DRY_RUN` |
+| `--force` | Re-install even if the version matches |
 | `--skip <phase>` | Skip a phase (repeatable): `preinstall`, `scripts`, `postinstall`, `scalepoint`, `apps` |
 | `--steps <spec>` | Run only listed phases: `1,3,4` or `1-3` |
 | `--no-color` | Disable colored output |
@@ -69,7 +69,7 @@ exactly as before (no added blank lines), so scripting stays byte-stable.
 2. Configure it (masked input):

   ```bash
-   pos config ai          # enter AI_API_KEY (or AI_GEMINI_API_KEY)
+   pos config ai          # enter AI_GEMINI_API_KEY
   ```

 3. Test:
@@ -81,7 +81,10 @@ exactly as before (no added blank lines), so scripting stays byte-stable.
   ```

 `ai.env` lives at `~/.config/linux_post_install/ai.env` (chmod 600); `pos config ai`
-is the only place the key is written. The key is never printed by `pos`.
+is where the provider keys are written, and keys are never printed by `pos`. The
+legacy shared `AI_API_KEY` is still honored as a fallback when the provider's own
+key is unset — set it via the shell environment or by hand-editing `ai.env` (it is
+not part of the `pos config ai` prompt).

 ## OpenRouter — many providers, one key

@@ -98,7 +101,7 @@ pos ai openrouter ask "hi"
 Configure the API key:

 ```bash
-pos config ai              # enter AI_API_KEY (or OPENROUTER_API_KEY)
+pos config ai              # enter OPENROUTER_API_KEY
 ```

 The default model is `openrouter/auto` (OpenRouter picks the best available
@@ -3,26 +3,34 @@
 Download audio and video from the web via `yt-dlp`, auto-classify URLs,
 sync your library to a USB stick, and keep YouTube channels incrementally
 up to date.
-Tools: `grab`, `mp3`, `mp4`, `sync`, `ytsync`.
+Tools: `yt mp3`, `yt mp4`, `yt grab`, `yt subtitles`, `sync`, `ytsync`.
+
+The YouTube download tools live under `pos media yt` (`mp3`, `mp4`, `grab`,
+`subtitles`, `ytsync`). The legacy standalone names `pos media mp3`, `pos media
+mp4` and `pos media grab` still work — they are thin forwarders to the `yt`
+forms.

 | Tool | What it does |
 |------|--------------|
-| `pos media grab` | Auto-classify URL and download as audio or video |
-| `pos media mp3` | Download audio, convert to MP3 |
-| `pos media mp4` | Download video with smart/interactive format selection |
+| `pos media yt mp3` | Download audio, convert to MP3 |
+| `pos media yt mp4` | Download video with smart/interactive format selection |
+| `pos media yt grab` | Auto-classify URL and download as audio or video |
+| `pos media yt subtitles` | Extract subtitles/captions from a URL |
+| `pos media yt ytsync` | Forwarder → `pos media ytsync` |
 | `pos media sync` | Incrementally copy `~/Music` onto a USB stick (mp3/mp4) |
 | `pos media ytsync` | Track YouTube channels/playlists and download only new videos into `~/Videos` |

-Requires `yt-dlp` and `ffmpeg` (`sudo apt install yt-dlp ffmpeg`); the tools
-fail with a clean error message instead of a raw `command not found` if either
-is missing.
+Requires `yt-dlp` and `ffmpeg` (`sudo apt install yt-dlp ffmpeg`) for `mp3`/
+`mp4`/`grab`; `subtitles` needs only `yt-dlp` (no ffmpeg). The tools fail with a
+clean error message instead of a raw `command not found` if a dependency is
+missing.

 ---

-## `pos media mp3` — audio as MP3
+## `pos media yt mp3` — audio as MP3

 ```bash
-pos media mp3 <url>
+pos media yt mp3 <url>        # or the legacy: pos media mp3 <url>
 ```

 Extracts and converts the audio track to MP3 in `~/Music/`. With `--by-artist`
@@ -30,8 +38,8 @@ files land in `~/Music/<artist>/<title>.mp3` (falls back to the uploader name
 when there's no artist tag), so a library stays organized.

 ```bash
-pos media mp3 https://youtube.com/watch?v=dQw4w9WgXcQ
-pos media mp3 --by-artist https://youtu.be/dQw4w9WgXcQ
+pos media yt mp3 https://youtube.com/watch?v=dQw4w9WgXcQ
+pos media yt mp3 --by-artist https://youtu.be/dQw4w9WgXcQ
 ```

 MP3s are encoded at best quality with title/artist/album/date/chapters embedded
@@ -48,15 +56,15 @@ cover art as a JPEG thumbnail. Existing files are never overwritten.

 **Recipe:** batch — loop over a list of URLs:
 ```bash
-while read -r url; do pos media mp3 --by-artist "$url"; done < urls.txt
+while read -r url; do pos media yt mp3 --by-artist "$url"; done < urls.txt
 ```

 ---

-## `pos media mp4` — video with smart format choice
+## `pos media yt mp4` — video with smart format choice

 ```bash
-pos media mp4 <url>
+pos media yt mp4 <url>        # or the legacy: pos media mp4 <url>
 ```

 Without a format flag, the available formats are shown as a **short curated
@@ -77,8 +85,8 @@ Non-interactive (scripting-friendly):
 | `--dry-run` | Print the yt-dlp command without running it |

 ```bash
-pos media mp4 --best https://youtube.com/watch?v=dQw4w9WgXcQ
-pos media mp4 -f 22 https://youtube.com/watch?v=dQw4w9WgXcQ
+pos media yt mp4 --best https://youtube.com/watch?v=dQw4w9WgXcQ
+pos media yt mp4 -f 22 https://youtube.com/watch?v=dQw4w9WgXcQ
 ```

 Videos merge to MP4 with metadata, chapters, subtitles (all languages) and the
@@ -90,13 +98,13 @@ video+audio and merges them.

 ---

-## `pos media grab` — auto-classify URL and download
+## `pos media yt grab` — auto-classify URL and download

 ```bash
-pos media grab <url>
+pos media yt grab <url>       # or the legacy: pos media grab <url>
 ```

-Smart URL classifier that routes to `pos media mp3` or `pos media mp4`
+Smart URL classifier that routes to `pos media yt mp3` or `pos media yt mp4`
 automatically based on the domain. Send a URL from your phone via Telegram and
 the bot downloads it to the right place without you thinking about it.

@@ -116,16 +124,16 @@ unrecognized domains is `video` — change it with `pos config grab` or set
 `GRAB_DEFAULT=audio` in `~/.config/linux_post_install/grab.env`.

 ```bash
-pos media grab https://music.youtube.com/watch?v=abc          # → ~/Music
-pos media grab https://youtube.com/watch?v=xyz                # → ~/Videos
-pos media grab --audio https://vimeo.com/123                  # force mp3
-pos media grab --worst https://youtu.be/abc                   # lowest quality
-pos media grab --dry-run https://soundcloud.com/artist/track  # preview only
+pos media yt grab https://music.youtube.com/watch?v=abc          # → ~/Music
+pos media yt grab https://youtube.com/watch?v=xyz                # → ~/Videos
+pos media yt grab --audio https://vimeo.com/123                  # force mp3
+pos media yt grab --worst https://youtu.be/abc                   # lowest quality
+pos media yt grab --dry-run https://soundcloud.com/artist/track  # preview only
 ```

-Non-interactive by design — `pos media mp4` receives `--best` by default so it
-never prompts for a format (critical for Telegram bot context where there's no
-TTY). Pass `--worst` if you want the smallest file.
+Non-interactive by design — `pos media yt mp4` receives `--best` by default so
+it never prompts for a format (critical for Telegram bot context where there's
+no TTY). Pass `--worst` if you want the smallest file.

 | Flag | Meaning |
 |------|---------|
@@ -140,6 +148,39 @@ TTY). Pass `--worst` if you want the smallest file.

 ---

+## `pos media yt subtitles` — extract subtitles/captions
+
+```bash
+pos media yt subtitles <url>
+```
+
+Downloads subtitles/captions from a URL via yt-dlp. Fetches manual captions and
+auto-generated captions by default (`--write-subs --write-auto-subs
+--sub-langs best` — "best" picks the manually-created track when available,
+otherwise the auto one). Output files land in the current directory as
+`<title>.<lang>.<ext>`.
+
+```bash
+pos media yt subtitles https://youtube.com/watch?v=dQw4w9WgXcQ
+pos media yt subtitles --lang en https://youtu.be/dQw4w9WgXcQ
+pos media yt subtitles --lang en,ar --format txt https://youtube.com/watch?v=dQw4w9WgXcQ
+```
+
+| Flag | Meaning |
+|------|---------|
+| `--lang <list>` | Subtitle languages, comma-separated (default `best`) — `en,ar` is passed as ONE `--sub-langs` arg |
+| `--format <fmt>` | `srt` (default) / `vtt` / `txt` — `txt` converts srt→txt (timestamps, seq numbers and HTML tags stripped) |
+| `--auto-only` | Only auto-generated captions (no manual subs) |
+| `-o, --output <dir>` | Output directory (default: current directory) |
+| `--list-subs` | List available subtitles for the URL and exit (probe only, no download) |
+| `--no-playlist` | Download only the single video |
+| `--dry-run` | Print the yt-dlp command without running it |
+
+If a video has no available subtitles the tool reports
+`unavailable subtitles for this video (try --list-subs to check)`.
+
+---
+
 ## `pos media sync` — music onto a USB stick

 ```bash
@@ -35,6 +35,7 @@ cd Linux_post_install
 | `--apps` | Interactive app picker after core install |
 | `--full` | Core install + all apps (non-interactive) |
 | `--dry-run` | Preview without executing |
+| `--force` | Re-install even if the version matches |
 | `--skip <phase>` | Skip a phase: `preinstall`, `scripts`, `postinstall`, `scalepoint`, `apps` |
 | `--steps <spec>` | Run only specific phases, e.g. `--steps 1,3` |
 | `--no-color` | Disable colored output |
@@ -266,7 +266,7 @@ MAIN_LOG="$LOG_DIR/pos.log"
 log_cmd() { echo "[$(date '+%Y-%m-%d %H:%M:%S')] $* → exit $2" >> "$MAIN_LOG"; }

 # Commands that read from stdin interactively — only log invocation
-INTERACTIVE_CMDS="docker-compose docker-vbox network-hotspot system-firewall media-mp4 media-sync system-backup system-uninstall share-usb-server share-smb-server share-smb-client share-nfs-client share-nfs-server communication-telegram-listener communication-matrix-listener ai ai-gemini ai-openrouter ai-llamacpp ai-alias system-schedule entertainment-config config"
+INTERACTIVE_CMDS="docker-compose docker-vbox network-hotspot system-firewall media-mp4 media-yt-mp4 media-sync system-backup system-uninstall share-usb-server share-smb-server share-smb-client share-nfs-client share-nfs-server communication-telegram-listener communication-matrix-listener ai ai-gemini ai-openrouter ai-llamacpp ai-alias system-schedule entertainment-config config"

 for ((i=n-1; i>=0; i--)); do
    cmd="pos"
@@ -156,10 +156,14 @@ load_config() {
 resolve_key() {
    load_config
    local p="${PROVIDER:-gemini}"
-    # Each provider has its own API key — set AI_API_KEY internally for adapters
+    # Provider-specific key wins (leakage guard); legacy shared AI_API_KEY is a
+    # read-only fallback when the provider's own key is empty — load_config/env
+    # already exported it (env-wins), so never overwrite it here.
    case "$p" in
-        gemini)     [ -n "${AI_GEMINI_API_KEY:-}" ] && export AI_API_KEY="$AI_GEMINI_API_KEY" && return 0 ;;
-        openrouter) [ -n "${OPENROUTER_API_KEY:-}" ] && export AI_API_KEY="$OPENROUTER_API_KEY" && return 0 ;;
+        gemini)     [ -n "${AI_GEMINI_API_KEY:-}" ] && export AI_API_KEY="$AI_GEMINI_API_KEY" && return 0
+                    [ -n "${AI_API_KEY:-}" ] && return 0 ;;
+        openrouter) [ -n "${OPENROUTER_API_KEY:-}" ] && export AI_API_KEY="$OPENROUTER_API_KEY" && return 0
+                    [ -n "${AI_API_KEY:-}" ] && return 0 ;;
        llamacpp)   return 0 ;;  # No API key needed for local server
    esac
    return 1
@@ -626,9 +630,10 @@ cmd_providers() {
        [ -n "$pmodel" ] || pmodel="unknown"
        # Check if API key exists for this provider
        configured="not configured"
+        # Same key set as resolve_key(): provider key, or legacy AI_API_KEY fallback
        case "$name" in
-            gemini)     [ -n "${AI_GEMINI_API_KEY:-}" ] && configured="configured" ;;
-            openrouter) [ -n "${OPENROUTER_API_KEY:-}" ] && configured="configured" ;;
+            gemini)     { [ -n "${AI_GEMINI_API_KEY:-}" ] || [ -n "${AI_API_KEY:-}" ]; } && configured="configured" ;;
+            openrouter) { [ -n "${OPENROUTER_API_KEY:-}" ] || [ -n "${AI_API_KEY:-}" ]; } && configured="configured" ;;
            llamacpp)   configured="configured" ;;  # Local server — always configured
        esac
        current=""
@@ -1,219 +1,5 @@
 #!/usr/bin/env bash
 set -euo pipefail
 # POS: media grab — Auto-download URL as audio or video (classify + route)
-# POS_FLAGS: --audio --video --best --worst --output --no-playlist --cookies --dry-run
-# POS_CONFIG: grab | grab.env | GRAB_DEFAULT=:Default mode for unknown domains (video or audio, default video)
-
-source "$(dirname "$0")/../lib/common.sh" 2>/dev/null || source "$(dirname "$0")/common.sh"
-
-# Shared config loader (canonical KEY=VALUE parser, env-wins precedence)
-source "$(dirname "$0")/../lib/config-ui.sh" 2>/dev/null || source "$(dirname "$0")/config-ui.sh"
-
-# Load grab.env config (env-seam: GRAB_DEFAULT)
-load_grab_config() {
-    load_env_file "$CONFIG_DIR/grab.env"
-}
-
-load_grab_config
-
-# ── URL classification ─────────────────────────────────────────
-classify_url() {
-    local url="$1" mode="${GRAB_DEFAULT:-video}"
-    case "$url" in
-        *music.youtube.com*)  echo "audio" ;;
-        *soundcloud.com*)     echo "audio" ;;
-        *bandcamp.com*)       echo "audio" ;;
-        *youtube.com*|*youtu.be*) echo "video" ;;
-        *vimeo.com*)          echo "video" ;;
-        *twitch.tv*)          echo "video" ;;
-        *)                    echo "$mode" ;;
-    esac
-}
-
-usage() {
-    cat <<EOF
-Usage: pos media grab [options] <url>
-
-Auto-download a URL as audio or video. Classifies the domain and delegates
-to 'pos media mp3' (audio) or 'pos media mp4' (video).
-
-Options:
-  --audio               Force audio (mp3) download
-  --video               Force video (mp4) download
-  --best                Best quality for video (default for non-interactive)
-  --worst               Lowest quality for video
-  -o, --output <dir>    Output directory (passed to mp3/mp4)
-  --no-playlist         Download only the single video
-  --cookies <file>      Netscape cookies.txt for age-gated content
-  --dry-run             Print the command that would run, don't execute
-  -h, --help            This help
-
-Examples:
-  pos media grab https://music.youtube.com/watch?v=abc
-  pos media grab https://youtube.com/watch?v=xyz
-  pos media grab --audio https://vimeo.com/123
-  pos media grab --worst https://youtu.be/abc
-  pos media grab --dry-run https://soundcloud.com/artist/track
-EOF
-    exit 0
-}
-
-# ── Arg parsing ────────────────────────────────────────────────
-URL=""
-FORCE_AUDIO=0
-FORCE_VIDEO=0
-BEST=0
-WORST=0
-DRY_RUN=0
-EXTRA_ARGS=()
-
-while [[ $# -gt 0 ]]; do
-    case "$1" in
-        -h|--help) usage ;;
-        --audio) FORCE_AUDIO=1; shift ;;
-        --video) FORCE_VIDEO=1; shift ;;
-        --best)  BEST=1; shift ;;
-        --worst) WORST=1; shift ;;
-        -o|--output)
-            [ $# -ge 2 ] || err "pos media grab: --output needs a value"
-            EXTRA_ARGS+=(--output "$2"); shift 2 ;;
-        --no-playlist) EXTRA_ARGS+=(--no-playlist); shift ;;
-        --cookies)
-            [ $# -ge 2 ] || err "pos media grab: --cookies needs a value"
-            EXTRA_ARGS+=(--cookies "$2"); shift 2 ;;
-        --dry-run) DRY_RUN=1; shift ;;
-        -*) err "pos media grab: Unknown option: $1 (see --help)" ;;
-        *)
-            [ -z "$URL" ] && URL="$1" && shift || err "pos media grab: Unexpected argument: $1" ;;
-    esac
-done
-
-[ -n "$URL" ] || usage
-
-# Validate URL scheme
-case "$URL" in
-    http://*|https://*) ;;
-    *) err "pos media grab: not a valid URL: $URL (must start with http:// or https://)" ;;
-esac
-
-# Validate mutually exclusive overrides
-[ "$FORCE_AUDIO" -eq 1 ] && [ "$FORCE_VIDEO" -eq 1 ] && \
-    err "pos media grab: --audio and --video are mutually exclusive"
-[ "$BEST" -eq 1 ] && [ "$WORST" -eq 1 ] && \
-    err "pos media grab: --best and --worst are mutually exclusive"
-
-# ── Classification ─────────────────────────────────────────────
-mode=""
-if [ "$FORCE_AUDIO" -eq 1 ]; then
-    mode="audio"
-elif [ "$FORCE_VIDEO" -eq 1 ]; then
-    mode="video"
-else
-    mode="$(classify_url "$URL")"
-fi
-
-# ── Build delegated command ────────────────────────────────────
-DELEGATE_ARGS=()
-
-if [ "$mode" = "audio" ]; then
-    DELEGATE_ARGS=(pos media mp3 "${EXTRA_ARGS[@]}")
-else
-    # mp4 route: --best by default (non-interactive), --worst if user passes it
-    if [ "$WORST" -eq 1 ]; then
-        DELEGATE_ARGS=(pos media mp4 --worst "${EXTRA_ARGS[@]}")
-    else
-        DELEGATE_ARGS=(pos media mp4 --best "${EXTRA_ARGS[@]}")
-    fi
-fi
-
-# ── Dry run ────────────────────────────────────────────────────
-if [ "$DRY_RUN" -eq 1 ]; then
-    echo "${DELEGATE_ARGS[*]} $URL"
-    exit 0
-fi
-
-# ── Execute ────────────────────────────────────────────────────
-output=""
-rc=0
-if output=$("${DELEGATE_ARGS[@]}" "$URL" 2>&1); then
-    rc=0
-else
-    rc=$?
-fi
-
-if [ "$rc" -ne 0 ]; then
-    # Summarize stderr for the user
-    summary="$(printf '%s' "$output" | grep -i 'error\|fail' | head -1 || true)"
-    [ -z "$summary" ] && summary="exit code $rc"
-    err "pos media grab: ❌ Download failed: $summary"
-fi
-
-# ── Metadata + summary ────────────────────────────────────────
-title=""
-duration=""
-file_path=""
-
-# Determine expected output directory
-if [ "$mode" = "audio" ]; then
-    out_dir="$HOME/Music"
-    for (( i=0; i<${#EXTRA_ARGS[@]}; i++ )); do
-        if [ "${EXTRA_ARGS[$i]}" = "--output" ] && [ $(( i + 1 )) -lt ${#EXTRA_ARGS[@]} ]; then
-            out_dir="${EXTRA_ARGS[$(( i + 1 ))]}"
-            break
-        fi
-    done
-    file_ext="mp3"
-else
-    out_dir="$HOME/Videos"
-    for (( i=0; i<${#EXTRA_ARGS[@]}; i++ )); do
-        if [ "${EXTRA_ARGS[$i]}" = "--output" ] && [ $(( i + 1 )) -lt ${#EXTRA_ARGS[@]} ]; then
-            out_dir="${EXTRA_ARGS[$(( i + 1 ))]}"
-            break
-        fi
-    done
-    file_ext="mp4"
-fi
-
-# Fetch metadata (fast, no download)
-if command -v yt-dlp &>/dev/null; then
-    meta="$(yt-dlp --print title --print duration_string --no-warnings "$URL" 2>/dev/null || true)"
-    title="$(printf '%s' "$meta" | sed -n '1p')"
-    duration="$(printf '%s' "$meta" | sed -n '2p')"
-fi
-
-# Find the downloaded file (most recent matching extension in out_dir)
-if [ -d "$out_dir" ]; then
-    file_path="$(find "$out_dir" -maxdepth 1 -name "*.$file_ext" -printf '%T@ %p\n' 2>/dev/null \
-        | sort -rn | head -1 | cut -d' ' -f2- || true)"
-fi
-
-# Build summary
-[ -z "$title" ] && title="$(basename "$URL" | sed 's/[?#].*//')"
-[ -z "$duration" ] && duration="?"
-
-if [ "$mode" = "audio" ]; then
-    emoji="🎵"
-else
-    emoji="🎬"
-fi
-
-echo "$emoji Downloaded: $title ($duration)"
-
-if [ -n "$file_path" ] && [ -f "$file_path" ]; then
-    file_size="$(stat --printf='%s' "$file_path" 2>/dev/null || echo "0")"
-    # Format size in human-readable form
-    if [ "$file_size" -ge 1073741824 ]; then
-        size_human="$(awk "BEGIN { printf \"%.1f GB\", $file_size / 1073741824 }")"
-    elif [ "$file_size" -ge 1048576 ]; then
-        size_human="$(awk "BEGIN { printf \"%.1f MB\", $file_size / 1048576 }")"
-    elif [ "$file_size" -ge 1024 ]; then
-        size_human="$(awk "BEGIN { printf \"%.1f KB\", $file_size / 1024 }")"
-    else
-        size_human="${file_size} B"
-    fi
-    # Show path relative to HOME
-    rel_path="${file_path/#$HOME/\~}"
-    echo "📁 $rel_path ($size_human)"
-else
-    echo "📁 $out_dir/ ($file_ext)"
-fi
+# -h|--help forwarded via exec below
+exec pos media yt grab "$@"
@@ -1,86 +1,5 @@
 #!/usr/bin/env bash
 set -euo pipefail
 # POS: media mp3 — Download audio as MP3 (yt-dlp)
-# POS_FLAGS: --output --no-playlist --cookies --by-artist --dry-run
-
-source "$(dirname "$0")/../lib/common.sh" 2>/dev/null || source "$(dirname "$0")/common.sh"
-
-# --dry-run is parsed before the deps guards (below): it previews the yt-dlp
-# command without requiring yt-dlp/ffmpeg to be installed.
-DRY_RUN=0
-for arg in "$@"; do
-    [ "$arg" = "--dry-run" ] && DRY_RUN=1
-done
-
-# Deps guards sit before -h|--help (help also errors on a box missing the deps).
-if [ "$DRY_RUN" -eq 0 ]; then
-    command -v yt-dlp &>/dev/null || err "yt-dlp not found — install it with: sudo apt install yt-dlp"
-    command -v ffmpeg &>/dev/null || err "ffmpeg not found (needed for MP3 conversion) — install it with: sudo apt install ffmpeg"
-fi
-
-OUT_DIR="$HOME/Music"
-BY_ARTIST=0
-EXTRA_ARGS=()
-
-usage() {
-    cat <<EOF
-Usage: pos media mp3 [options] <url>
-
-Download audio from a URL and convert to MP3 via yt-dlp.
-
-Options:
-  -o, --output <dir>    Output directory (default: $OUT_DIR)
-  --by-artist           Organize as <dir>/<artist>/<title>.mp3
-  --no-playlist         Download only the single video
-  --cookies <file>      Netscape cookies.txt for age-gated content
-  --dry-run             Print the yt-dlp command without running it
-  -h, --help            This help
-
-Examples:
-  pos media mp3 https://youtube.com/watch?v=dQw4w9WgXcQ
-  pos media mp3 --by-artist --no-playlist https://youtu.be/dQw4w9WgXcQ
-  pos media mp3 --cookies ~/cookies.txt https://vimeo.com/123
-EOF
-    exit 0
-}
-
-URL=""
-while [[ $# -gt 0 ]]; do
-    case "$1" in
-        -h|--help) usage ;;
-        -o|--output)
-            [ $# -ge 2 ] || err "--output needs a value"
-            OUT_DIR="$2"; shift 2 ;;
-        --by-artist) BY_ARTIST=1; shift ;;
-        --no-playlist) EXTRA_ARGS+=(--no-playlist); shift ;;
-        --cookies)
-            [ $# -ge 2 ] || err "--cookies needs a value"
-            [ -f "$2" ] || err "cookies file not found: $2"
-            EXTRA_ARGS+=(--cookies "$2"); shift 2 ;;
-        --dry-run) DRY_RUN=1; shift ;;
-        -*) err "Unknown option: $1 (see --help)" ;;
-        *)
-            [ -z "$URL" ] && URL="$1" && shift || err "Unexpected argument: $1" ;;
-    esac
-done
-[ -n "$URL" ] || usage
-
-if [ "$BY_ARTIST" -eq 1 ]; then
-    OUT_TEMPLATE="$OUT_DIR/%(artist,uploader)s/%(title)s.%(ext)s"
-else
-    OUT_TEMPLATE="$OUT_DIR/%(title)s.%(ext)s"
-fi
-
-args=(yt-dlp -x --audio-format mp3 --audio-quality 0
-    --embed-metadata --embed-chapters
-    --embed-thumbnail --convert-thumbnails jpg
-    --parse-metadata "%(artist,uploader)s:%(artist)s"
-    --no-overwrites
-    -o "$OUT_TEMPLATE"
-    "${EXTRA_ARGS[@]}" "$URL")
-
-if [ "$DRY_RUN" -eq 1 ]; then
-    echo "yt-dlp ${args[*]:1}"
-else
-    spawn "downloading audio → $OUT_DIR" "${args[@]}"
-fi
+# -h|--help forwarded via exec below
+exec pos media yt mp3 "$@"
@@ -1,132 +1,5 @@
 #!/usr/bin/env bash
 set -euo pipefail
 # POS: media mp4 — Download video as MP4 (smart/interactive format select)
-# POS_FLAGS: --format --best --worst --output --no-playlist --cookies --dry-run
-
-source "$(dirname "$0")/../lib/common.sh" 2>/dev/null || source "$(dirname "$0")/common.sh"
-
-# --dry-run is parsed before the deps guards (below): it previews the yt-dlp
-# command without requiring yt-dlp/ffmpeg to be installed.
-DRY_RUN=0
-for arg in "$@"; do
-    [ "$arg" = "--dry-run" ] && DRY_RUN=1
-done
-
-# Deps guards sit before -h|--help (help also errors on a box missing the deps).
-if [ "$DRY_RUN" -eq 0 ]; then
-    command -v yt-dlp &>/dev/null || err "yt-dlp not found — install it with: sudo apt install yt-dlp"
-    command -v ffmpeg &>/dev/null || err "ffmpeg not found (needed for MP4 merge) — install it with: sudo apt install ffmpeg"
-fi
-
-OUT_DIR="$HOME/Videos"
-FORMAT=""
-BEST=0
-WORST=0
-EXTRA_ARGS=()
-
-usage() {
-    cat <<EOF
-Usage: pos media mp4 [options] <url>
-
-Download video from a URL via yt-dlp. Without -f/--best/--worst, formats are
-listed and picked interactively.
-
-Options:
-  -f, --format <id>     Download that format id directly (no prompt)
-  --best                Best video + audio (no prompt)
-  --worst               Lowest quality (no prompt)
-  -o, --output <dir>    Output directory (default: $OUT_DIR)
-  --no-playlist         Download only the single video
-  --cookies <file>      Netscape cookies.txt for age-gated content
-  --dry-run             Print the yt-dlp command without running it
-  -h, --help            This help
-
-Examples:
-  pos media mp4 https://youtube.com/watch?v=dQw4w9WgXcQ
-  pos media mp4 --best https://youtube.com/watch?v=dQw4w9WgXcQ
-  pos media mp4 -f 22 https://youtube.com/watch?v=dQw4w9WgXcQ
-EOF
-    exit 0
-}
-
-URL=""
-while [[ $# -gt 0 ]]; do
-    case "$1" in
-        -h|--help) usage ;;
-        -f|--format)
-            [ $# -ge 2 ] || err "--format needs a value"
-            FORMAT="$2"; shift 2 ;;
-        --best) BEST=1; shift ;;
-        --worst) WORST=1; shift ;;
-        -o|--output)
-            [ $# -ge 2 ] || err "--output needs a value"
-            OUT_DIR="$2"; shift 2 ;;
-        --no-playlist) EXTRA_ARGS+=(--no-playlist); shift ;;
-        --cookies)
-            [ $# -ge 2 ] || err "--cookies needs a value"
-            [ -f "$2" ] || err "cookies file not found: $2"
-            EXTRA_ARGS+=(--cookies "$2"); shift 2 ;;
-        --dry-run) DRY_RUN=1; shift ;;
-        -*) err "Unknown option: $1 (see --help)" ;;
-        *)
-            [ -z "$URL" ] && URL="$1" && shift || err "Unexpected argument: $1" ;;
-    esac
-done
-[ -n "$URL" ] || usage
-
-[ -n "$FORMAT" ] && { [ "$BEST" -eq 1 ] || [ "$WORST" -eq 1 ]; } \
-    && err "--format and --best/--worst are mutually exclusive"
-[ "$BEST" -eq 1 ] && [ "$WORST" -eq 1 ] && err "--best and --worst are mutually exclusive"
-
-# Resolve the format selector: explicit flag → smart preset → interactive.
-# The curated table goes to stderr; stdout carries ONLY the chosen format id
-# (same ui_pick lesson — a $(...) capture must not swallow the menu).
-fmt_spec=""
-if [ -n "$FORMAT" ]; then
-    fmt_spec="$FORMAT"
-elif [ "$BEST" -eq 1 ]; then
-    fmt_spec="bestvideo*+bestaudio/best"
-elif [ "$WORST" -eq 1 ]; then
-    fmt_spec="worst"
-else
-    table="$(yt-dlp -F "$URL" 2>&1)" || {
-        echo "ERROR: no formats listed (unsupported site or age-gated content)" >&2
-        exit 1
-    }
-    printf '%s' "$table" | awk -F'[[:space:]][[:space:]]+' '
-        NR <= 2 { print; next }
-        $0 ~ /^-+$/ { print; next }
-        $0 ~ /audio only/ && $0 !~ /storyboard/ && $1 !~ /^sb/ { print "  [audio] " $0; next }
-        $0 ~ /video only/ && $1 !~ /^sb/ { print "  [video] " $0; next }
-        $1 ~ /^[0-9]+$/ && $2 ~ /^(mp4|webm)$/ && $3 ~ /x/ { print "  [combo] " $0 }
-    ' >&2
-    echo >&2
-    read -rp "Format ID ('best'/'worst'/empty = best): " chosen
-    case "${chosen:-best}" in
-        best) fmt_spec="bestvideo*+bestaudio/best" ;;
-        worst) fmt_spec="worst" ;;
-        *)
-            if printf '%s' "$table" | grep -qE "^[[:space:]]*${chosen}[[:space:]]"; then
-                fmt_spec="$chosen"
-            else
-                echo "ERROR: unknown format id '$chosen'" >&2
-                exit 1
-            fi
-            ;;
-    esac
-fi
-
-args=(yt-dlp -f "$fmt_spec"
-    --merge-output-format mp4
-    --embed-metadata --embed-chapters
-    --embed-subs --sub-langs all
-    --embed-thumbnail
-    --no-overwrites
-    -o "$OUT_DIR/%(title)s.%(ext)s"
-    "${EXTRA_ARGS[@]}" "$URL")
-
-if [ "$DRY_RUN" -eq 1 ]; then
-    echo "yt-dlp ${args[*]:1}"
-else
-    spawn "downloading video → $OUT_DIR" "${args[@]}"
-fi
+# -h|--help forwarded via exec below
+exec pos media yt mp4 "$@"
@@ -0,0 +1,33 @@
+#!/usr/bin/env bash
+set -euo pipefail
+# POS: media yt — YouTube download tools (mp3/mp4/grab/ytsync/subtitles)
+# POS_SUBCMDS: mp3 mp4 grab ytsync subtitles
+source "$(dirname "$0")/../lib/common.sh" 2>/dev/null || source "$(dirname "$0")/common.sh"
+
+usage() {
+    cat <<'EOF'
+Usage: pos media yt <command> [args]
+
+YouTube download tools: audio, video, auto-grab, subtitles, channel sync.
+
+Commands:
+  mp3 <url>          Download audio as MP3
+  mp4 <url>          Download video as MP4 (interactive format select)
+  grab <url>         Auto-download as audio or video
+  ytsync [cmd]       Incremental YouTube channel sync
+  subtitles <url>    Extract subtitles/captions
+
+Options:
+  -h, --help         This help
+
+Run 'pos media yt <command> --help' for details.
+EOF
+    exit 0
+}
+
+case "${1:-}" in
+    -h|--help|"") usage ;;
+esac
+# Subcommands are resolved by the dispatcher via pos-media-yt-<sub> files.
+# This file only handles bare 'pos media yt' (help) and unknown args.
+err "unknown yt command: $1 (see 'pos media yt --help')"
@@ -0,0 +1,208 @@
+#!/usr/bin/env bash
+set -euo pipefail
+# POS: media yt-grab — Auto-download URL as audio or video (classify + route)
+# POS_FLAGS: --audio --video --best --worst --output --no-playlist --cookies --dry-run
+# POS_CONFIG: grab | grab.env | GRAB_DEFAULT=:Default mode for unknown domains (video or audio, default video)
+
+source "$(dirname "$0")/../lib/common.sh" 2>/dev/null || source "$(dirname "$0")/common.sh"
+
+# Shared config loader (canonical KEY=VALUE parser, env-wins precedence)
+source "$(dirname "$0")/../lib/config-ui.sh" 2>/dev/null || source "$(dirname "$0")/config-ui.sh"
+
+# Shared yt helpers (classify_url, yt_validate_url, yt_check_deps, yt_echo_cmd)
+source "$(dirname "$0")/../lib/yt-lib.sh" 2>/dev/null || source "$(dirname "$0")/yt-lib.sh"
+
+# Load grab.env config (env-seam: GRAB_DEFAULT)
+load_grab_config() {
+    load_env_file "$CONFIG_DIR/grab.env"
+}
+
+load_grab_config
+
+usage() {
+    cat <<EOF
+Usage: pos media yt grab [options] <url>
+
+Auto-download a URL as audio or video. Classifies the domain and delegates
+to 'pos media yt mp3' (audio) or 'pos media yt mp4' (video).
+
+Options:
+  --audio               Force audio (mp3) download
+  --video               Force video (mp4) download
+  --best                Best quality for video (default for non-interactive)
+  --worst               Lowest quality for video
+  -o, --output <dir>    Output directory (passed to mp3/mp4)
+  --no-playlist         Download only the single video
+  --cookies <file>      Netscape cookies.txt for age-gated content
+  --dry-run             Print the command that would run, don't execute
+  -h, --help            This help
+
+Examples:
+  pos media yt grab https://music.youtube.com/watch?v=abc
+  pos media yt grab https://youtube.com/watch?v=xyz
+  pos media yt grab --audio https://vimeo.com/123
+  pos media yt grab --worst https://youtu.be/abc
+  pos media yt grab --dry-run https://soundcloud.com/artist/track
+
+The legacy spelling 'pos media grab' still works (forwarder) and is equivalent.
+EOF
+    exit 0
+}
+
+# ── Arg parsing ────────────────────────────────────────────────
+URL=""
+FORCE_AUDIO=0
+FORCE_VIDEO=0
+BEST=0
+WORST=0
+DRY_RUN=0
+EXTRA_ARGS=()
+
+while [[ $# -gt 0 ]]; do
+    case "$1" in
+        -h|--help) usage ;;
+        --audio) FORCE_AUDIO=1; shift ;;
+        --video) FORCE_VIDEO=1; shift ;;
+        --best)  BEST=1; shift ;;
+        --worst) WORST=1; shift ;;
+        -o|--output)
+            [ $# -ge 2 ] || err "yt-grab: --output needs a value"
+            EXTRA_ARGS+=(--output "$2"); shift 2 ;;
+        --no-playlist) EXTRA_ARGS+=(--no-playlist); shift ;;
+        --cookies)
+            [ $# -ge 2 ] || err "yt-grab: --cookies needs a value"
+            EXTRA_ARGS+=(--cookies "$2"); shift 2 ;;
+        --dry-run) DRY_RUN=1; shift ;;
+        -*) err "yt-grab: Unknown option: $1 (see --help)" ;;
+        *)
+            [ -z "$URL" ] && URL="$1" && shift || err "yt-grab: Unexpected argument: $1" ;;
+    esac
+done
+
+[ -n "$URL" ] || usage
+
+# Validate URL scheme
+yt_validate_url "$URL" 2>/dev/null || \
+    err "yt-grab: not a valid URL: $URL (must start with http:// or https://)"
+
+# Validate mutually exclusive overrides
+[ "$FORCE_AUDIO" -eq 1 ] && [ "$FORCE_VIDEO" -eq 1 ] && \
+    err "yt-grab: --audio and --video are mutually exclusive"
+[ "$BEST" -eq 1 ] && [ "$WORST" -eq 1 ] && \
+    err "yt-grab: --best and --worst are mutually exclusive"
+
+# ── Classification ─────────────────────────────────────────────
+mode=""
+if [ "$FORCE_AUDIO" -eq 1 ]; then
+    mode="audio"
+elif [ "$FORCE_VIDEO" -eq 1 ]; then
+    mode="video"
+else
+    mode="$(classify_url "$URL")"
+fi
+
+# ── Build delegated command ────────────────────────────────────
+DELEGATE_ARGS=()
+
+if [ "$mode" = "audio" ]; then
+    DELEGATE_ARGS=(pos media yt mp3 "${EXTRA_ARGS[@]}")
+else
+    # mp4 route: --best by default (non-interactive), --worst if user passes it
+    if [ "$WORST" -eq 1 ]; then
+        DELEGATE_ARGS=(pos media yt mp4 --worst "${EXTRA_ARGS[@]}")
+    else
+        DELEGATE_ARGS=(pos media yt mp4 --best "${EXTRA_ARGS[@]}")
+    fi
+fi
+
+# ── Dry run ────────────────────────────────────────────────────
+if [ "$DRY_RUN" -eq 1 ]; then
+    echo "${DELEGATE_ARGS[*]} $URL"
+    exit 0
+fi
+
+# ── Execute ────────────────────────────────────────────────────
+output=""
+rc=0
+if output=$("${DELEGATE_ARGS[@]}" "$URL" 2>&1); then
+    rc=0
+else
+    rc=$?
+fi
+
+if [ "$rc" -ne 0 ]; then
+    # Summarize stderr for the user
+    summary="$(printf '%s' "$output" | grep -i 'error\|fail' | head -1 || true)"
+    [ -z "$summary" ] && summary="exit code $rc"
+    err "yt-grab: ❌ Download failed: $summary"
+fi
+
+# ── Metadata + summary ────────────────────────────────────────
+title=""
+duration=""
+file_path=""
+
+# Determine expected output directory
+if [ "$mode" = "audio" ]; then
+    out_dir="$HOME/Music"
+    for (( i=0; i<${#EXTRA_ARGS[@]}; i++ )); do
+        if [ "${EXTRA_ARGS[$i]}" = "--output" ] && [ $(( i + 1 )) -lt ${#EXTRA_ARGS[@]} ]; then
+            out_dir="${EXTRA_ARGS[$(( i + 1 ))]}"
+            break
+        fi
+    done
+    file_ext="mp3"
+else
+    out_dir="$HOME/Videos"
+    for (( i=0; i<${#EXTRA_ARGS[@]}; i++ )); do
+        if [ "${EXTRA_ARGS[$i]}" = "--output" ] && [ $(( i + 1 )) -lt ${#EXTRA_ARGS[@]} ]; then
+            out_dir="${EXTRA_ARGS[$(( i + 1 ))]}"
+            break
+        fi
+    done
+    file_ext="mp4"
+fi
+
+# Fetch metadata (fast, no download)
+if command -v yt-dlp &>/dev/null; then
+    meta="$(yt-dlp --print title --print duration_string --no-warnings "$URL" 2>/dev/null || true)"
+    title="$(printf '%s' "$meta" | sed -n '1p')"
+    duration="$(printf '%s' "$meta" | sed -n '2p')"
+fi
+
+# Find the downloaded file (most recent matching extension in out_dir)
+if [ -d "$out_dir" ]; then
+    file_path="$(find "$out_dir" -maxdepth 1 -name "*.$file_ext" -printf '%T@ %p\n' 2>/dev/null \
+        | sort -rn | head -1 | cut -d' ' -f2- || true)"
+fi
+
+# Build summary
+[ -z "$title" ] && title="$(basename "$URL" | sed 's/[?#].*//')"
+[ -z "$duration" ] && duration="?"
+
+if [ "$mode" = "audio" ]; then
+    emoji="🎵"
+else
+    emoji="🎬"
+fi
+
+echo "$emoji Downloaded: $title ($duration)"
+
+if [ -n "$file_path" ] && [ -f "$file_path" ]; then
+    file_size="$(stat --printf='%s' "$file_path" 2>/dev/null || echo "0")"
+    # Format size in human-readable form
+    if [ "$file_size" -ge 1073741824 ]; then
+        size_human="$(awk "BEGIN { printf \"%.1f GB\", $file_size / 1073741824 }")"
+    elif [ "$file_size" -ge 1048576 ]; then
+        size_human="$(awk "BEGIN { printf \"%.1f MB\", $file_size / 1048576 }")"
+    elif [ "$file_size" -ge 1024 ]; then
+        size_human="$(awk "BEGIN { printf \"%.1f KB\", $file_size / 1024 }")"
+    else
+        size_human="${file_size} B"
+    fi
+    # Show path relative to HOME
+    rel_path="${file_path/#$HOME/\~}"
+    echo "📁 $rel_path ($size_human)"
+else
+    echo "📁 $out_dir/ ($file_ext)"
+fi
@@ -0,0 +1,86 @@
+#!/usr/bin/env bash
+set -euo pipefail
+# POS: media yt-mp3 — Download audio as MP3 (yt-dlp)
+# POS_FLAGS: --output --no-playlist --cookies --by-artist --dry-run
+
+source "$(dirname "$0")/../lib/common.sh" 2>/dev/null || source "$(dirname "$0")/common.sh"
+source "$(dirname "$0")/../lib/yt-lib.sh" 2>/dev/null || source "$(dirname "$0")/yt-lib.sh"
+
+# --dry-run is parsed before the deps guards (below): it previews the yt-dlp
+# command without requiring yt-dlp/ffmpeg to be installed.
+DRY_RUN=0
+for arg in "$@"; do
+    [ "$arg" = "--dry-run" ] && DRY_RUN=1
+done
+
+# Deps guards sit before -h|--help (help also errors on a box missing the deps).
+# yt_check_deps with dry-run=1 skips the dep checks (dry-run preview needs none).
+yt_check_deps "$DRY_RUN" "MP3 conversion"
+
+# Env seam: YT_OUT_DIR overrides the default (keeps HOME sandbox-compatible).
+OUT_DIR="${YT_OUT_DIR:-$HOME/Music}"
+BY_ARTIST=0
+EXTRA_ARGS=()
+
+usage() {
+    cat <<EOF
+Usage: pos media yt mp3 [options] <url>
+
+Download audio from a URL and convert to MP3 via yt-dlp.
+
+Options:
+  -o, --output <dir>    Output directory (default: $OUT_DIR)
+  --by-artist           Organize as <dir>/<artist>/<title>.mp3
+  --no-playlist         Download only the single video
+  --cookies <file>      Netscape cookies.txt for age-gated content
+  --dry-run             Print the yt-dlp command without running it
+  -h, --help            This help
+
+Examples:
+  pos media yt mp3 https://youtube.com/watch?v=dQw4w9WgXcQ
+  pos media yt mp3 --by-artist --no-playlist https://youtu.be/dQw4w9WgXcQ
+  pos media yt mp3 --cookies ~/cookies.txt https://vimeo.com/123
+EOF
+    exit 0
+}
+
+URL=""
+while [[ $# -gt 0 ]]; do
+    case "$1" in
+        -h|--help) usage ;;
+        -o|--output)
+            [ $# -ge 2 ] || err "--output needs a value"
+            OUT_DIR="$2"; shift 2 ;;
+        --by-artist) BY_ARTIST=1; shift ;;
+        --no-playlist) EXTRA_ARGS+=(--no-playlist); shift ;;
+        --cookies)
+            [ $# -ge 2 ] || err "--cookies needs a value"
+            [ -f "$2" ] || err "cookies file not found: $2"
+            EXTRA_ARGS+=(--cookies "$2"); shift 2 ;;
+        --dry-run) DRY_RUN=1; shift ;;
+        -*) err "Unknown option: $1 (see --help)" ;;
+        *)
+            [ -z "$URL" ] && URL="$1" && shift || err "Unexpected argument: $1" ;;
+    esac
+done
+[ -n "$URL" ] || usage
+
+if [ "$BY_ARTIST" -eq 1 ]; then
+    OUT_TEMPLATE="$OUT_DIR/%(artist,uploader)s/%(title)s.%(ext)s"
+else
+    OUT_TEMPLATE="$OUT_DIR/%(title)s.%(ext)s"
+fi
+
+args=(yt-dlp -x --audio-format mp3 --audio-quality 0
+    --embed-metadata --embed-chapters
+    --embed-thumbnail --convert-thumbnails jpg
+    --parse-metadata "%(artist,uploader)s:%(artist)s"
+    --no-overwrites
+    -o "$OUT_TEMPLATE"
+    "${EXTRA_ARGS[@]}" "$URL")
+
+if [ "$DRY_RUN" -eq 1 ]; then
+    echo "yt-dlp ${args[*]:1}"
+else
+    spawn "downloading audio → $OUT_DIR" "${args[@]}"
+fi
@@ -0,0 +1,132 @@
+#!/usr/bin/env bash
+set -euo pipefail
+# POS: media yt-mp4 — Download video as MP4 (smart/interactive format select)
+# POS_FLAGS: --format --best --worst --output --no-playlist --cookies --dry-run
+
+source "$(dirname "$0")/../lib/common.sh" 2>/dev/null || source "$(dirname "$0")/common.sh"
+source "$(dirname "$0")/../lib/yt-lib.sh" 2>/dev/null || source "$(dirname "$0")/yt-lib.sh"
+
+# --dry-run is parsed before the deps guards (below): it previews the yt-dlp
+# command without requiring yt-dlp/ffmpeg to be installed.
+DRY_RUN=0
+for arg in "$@"; do
+    [ "$arg" = "--dry-run" ] && DRY_RUN=1
+done
+
+# Deps guards sit before -h|--help (help also errors on a box missing the deps).
+# yt_check_deps with dry-run=1 skips the dep checks (dry-run preview needs none).
+yt_check_deps "$DRY_RUN" "MP4 merge"
+
+# Env seam: YT_OUT_DIR overrides the default (keeps HOME sandbox-compatible).
+OUT_DIR="${YT_OUT_DIR:-$HOME/Videos}"
+FORMAT=""
+BEST=0
+WORST=0
+EXTRA_ARGS=()
+
+usage() {
+    cat <<EOF
+Usage: pos media yt mp4 [options] <url>
+
+Download video from a URL via yt-dlp. Without -f/--best/--worst, formats are
+listed and picked interactively.
+
+Options:
+  -f, --format <id>     Download that format id directly (no prompt)
+  --best                Best video + audio (no prompt)
+  --worst               Lowest quality (no prompt)
+  -o, --output <dir>    Output directory (default: $OUT_DIR)
+  --no-playlist         Download only the single video
+  --cookies <file>      Netscape cookies.txt for age-gated content
+  --dry-run             Print the yt-dlp command without running it
+  -h, --help            This help
+
+Examples:
+  pos media yt mp4 https://youtube.com/watch?v=dQw4w9WgXcQ
+  pos media yt mp4 --best https://youtube.com/watch?v=dQw4w9WgXcQ
+  pos media yt mp4 -f 22 https://youtube.com/watch?v=dQw4w9WgXcQ
+EOF
+    exit 0
+}
+
+URL=""
+while [[ $# -gt 0 ]]; do
+    case "$1" in
+        -h|--help) usage ;;
+        -f|--format)
+            [ $# -ge 2 ] || err "--format needs a value"
+            FORMAT="$2"; shift 2 ;;
+        --best) BEST=1; shift ;;
+        --worst) WORST=1; shift ;;
+        -o|--output)
+            [ $# -ge 2 ] || err "--output needs a value"
+            OUT_DIR="$2"; shift 2 ;;
+        --no-playlist) EXTRA_ARGS+=(--no-playlist); shift ;;
+        --cookies)
+            [ $# -ge 2 ] || err "--cookies needs a value"
+            [ -f "$2" ] || err "cookies file not found: $2"
+            EXTRA_ARGS+=(--cookies "$2"); shift 2 ;;
+        --dry-run) DRY_RUN=1; shift ;;
+        -*) err "Unknown option: $1 (see --help)" ;;
+        *)
+            [ -z "$URL" ] && URL="$1" && shift || err "Unexpected argument: $1" ;;
+    esac
+done
+[ -n "$URL" ] || usage
+
+[ -n "$FORMAT" ] && { [ "$BEST" -eq 1 ] || [ "$WORST" -eq 1 ]; } \
+    && err "--format and --best/--worst are mutually exclusive"
+[ "$BEST" -eq 1 ] && [ "$WORST" -eq 1 ] && err "--best and --worst are mutually exclusive"
+
+# Resolve the format selector: explicit flag → smart preset → interactive.
+# The curated table goes to stderr; stdout carries ONLY the chosen format id
+# (same ui_pick lesson — a $(...) capture must not swallow the menu).
+fmt_spec=""
+if [ -n "$FORMAT" ]; then
+    fmt_spec="$FORMAT"
+elif [ "$BEST" -eq 1 ]; then
+    fmt_spec="bestvideo*+bestaudio/best"
+elif [ "$WORST" -eq 1 ]; then
+    fmt_spec="worst"
+else
+    table="$(yt-dlp -F "$URL" 2>&1)" || {
+        echo "ERROR: no formats listed (unsupported site or age-gated content)" >&2
+        exit 1
+    }
+    printf '%s' "$table" | awk -F'[[:space:]][[:space:]]+' '
+        NR <= 2 { print; next }
+        $0 ~ /^-+$/ { print; next }
+        $0 ~ /audio only/ && $0 !~ /storyboard/ && $1 !~ /^sb/ { print "  [audio] " $0; next }
+        $0 ~ /video only/ && $1 !~ /^sb/ { print "  [video] " $0; next }
+        $1 ~ /^[0-9]+$/ && $2 ~ /^(mp4|webm)$/ && $3 ~ /x/ { print "  [combo] " $0 }
+    ' >&2
+    echo >&2
+    read -rp "Format ID ('best'/'worst'/empty = best): " chosen
+    case "${chosen:-best}" in
+        best) fmt_spec="bestvideo*+bestaudio/best" ;;
+        worst) fmt_spec="worst" ;;
+        *)
+            if printf '%s' "$table" | grep -qE "^[[:space:]]*${chosen}[[:space:]]"; then
+                fmt_spec="$chosen"
+            else
+                echo "ERROR: unknown format id '$chosen'" >&2
+                exit 1
+            fi
+            ;;
+    esac
+fi
+
+args=(yt-dlp -f "$fmt_spec"
+    --merge-output-format mp4
+    --embed-metadata --embed-chapters
+    --embed-subs --sub-langs all
+    --embed-thumbnail
+    --no-overwrites
+    -o "$OUT_DIR/%(title)s.%(ext)s"
+    "${EXTRA_ARGS[@]}" "$URL")
+
+if [ "$DRY_RUN" -eq 1 ]; then
+    echo "yt-dlp ${args[*]:1}"
+else
+    spawn "downloading video → $OUT_DIR" "${args[@]}"
+fi
@@ -0,0 +1,169 @@
+#!/usr/bin/env bash
+set -euo pipefail
+# POS: media yt-subtitles — Extract subtitles/captions from a URL (yt-dlp)
+# POS_FLAGS: --lang --format --auto-only --output --list-subs --no-playlist --dry-run
+
+source "$(dirname "$0")/../lib/common.sh" 2>/dev/null || source "$(dirname "$0")/common.sh"
+source "$(dirname "$0")/../lib/yt-lib.sh" 2>/dev/null || source "$(dirname "$0")/yt-lib.sh"
+
+# --dry-run / --list-subs are parsed before the deps guards (below): dry-run
+# previews the yt-dlp command without requiring yt-dlp to be installed.
+DRY_RUN=0
+LIST_SUBS=0
+for arg in "$@"; do
+    [ "$arg" = "--dry-run" ] && DRY_RUN=1
+    [ "$arg" = "--list-subs" ] && LIST_SUBS=1
+done
+
+# Deps guards sit before -h|--help. Subtitles needs only yt-dlp (no ffmpeg).
+# dry-run skips the deps check entirely (preview needs no binary).
+if [ "$DRY_RUN" -eq 0 ]; then
+    command -v yt-dlp &>/dev/null || err "yt-dlp not found — install it with: sudo apt install yt-dlp"
+fi
+
+LANG_SPEC=""
+FMT="srt"
+AUTO_ONLY=0
+OUT_DIR=""
+NO_PLAYLIST=0
+
+usage() {
+    cat <<EOF
+Usage: pos media yt subtitles [options] <url>
+
+Extract subtitles/captions from a URL via yt-dlp. Fetches manual captions and
+auto-generated captions by default.
+
+Options:
+  --lang <list>         Subtitle languages (comma-separated), default: best
+  --format <fmt>        Output format: srt (default), vtt, or txt
+  --auto-only           Only auto-generated captions (no manual subs)
+  -o, --output <dir>    Output directory (default: current directory)
+  --list-subs           List available subtitles and exit (probe only)
+  --no-playlist         Download only the single video
+  --dry-run             Print the yt-dlp command without running it
+  -h, --help            This help
+
+Examples:
+  pos media yt subtitles https://youtube.com/watch?v=dQw4w9WgXcQ
+  pos media yt subtitles --lang en,ar https://youtube.com/watch?v=dQw4w9WgXcQ
+  pos media yt subtitles --format txt https://youtu.be/dQw4w9WgXcQ
+  pos media yt subtitles --list-subs https://youtube.com/watch?v=dQw4w9WgXcQ
+EOF
+    exit 0
+}
+
+# convert_srt_to_txt <srt-file> — strip SRT timestamps, seq numbers, HTML tags
+convert_srt_to_txt() {
+    local srt_file="$1" txt_file="${1%.srt}.txt"
+    sed '/^[0-9][0-9]:[0-9][0-9]/d; /^$/d; s/<[^>]*>//g' "$srt_file" > "$txt_file"
+}
+
+URL=""
+while [[ $# -gt 0 ]]; do
+    case "$1" in
+        -h|--help) usage ;;
+        --lang)
+            [ $# -ge 2 ] || err "--lang needs a value"
+            LANG_SPEC="$2"; shift 2 ;;
+        --format)
+            [ $# -ge 2 ] || err "--format needs a value"
+            case "$2" in
+                srt|vtt|txt) FMT="$2" ;;
+                *) err "unknown format '$2' (use srt, vtt, or txt)" ;;
+            esac
+            shift 2 ;;
+        --auto-only) AUTO_ONLY=1; shift ;;
+        -o|--output)
+            [ $# -ge 2 ] || err "--output needs a value"
+            OUT_DIR="$2"; shift 2 ;;
+        --list-subs) LIST_SUBS=1; shift ;;
+        --no-playlist) NO_PLAYLIST=1; shift ;;
+        --dry-run) DRY_RUN=1; shift ;;
+        -*) err "Unknown option: $1 (see --help)" ;;
+        *)
+            [ -z "$URL" ] && URL="$1" && shift || err "Unexpected argument: $1" ;;
+    esac
+done
+[ -n "$URL" ] || err "missing URL (see --help)"
+
+yt_validate_url "$URL" 2>/dev/null || err "not a valid URL: $URL (must start with http:// or https://)"
+
+# ── Build the yt-dlp command ─────────────────────────────────
+if [ "$LIST_SUBS" -eq 1 ]; then
+    args=(yt-dlp --list-subs "$URL")
+    if [ "$DRY_RUN" -eq 1 ]; then
+        yt_echo_cmd "${args[@]:1}"
+        exit 0
+    fi
+    spawn "listing subtitles" "${args[@]}"
+    exit 0
+fi
+
+# Output template
+OUT_TEMPLATE=""
+if [ -n "$OUT_DIR" ]; then
+    OUT_TEMPLATE="$OUT_DIR/%(title)s.%(sub_lang)s.%(ext)s"
+else
+    OUT_TEMPLATE="./%(title)s.%(sub_lang)s.%(ext)s"
+fi
+
+args=(yt-dlp)
+if [ "$AUTO_ONLY" -eq 1 ]; then
+    args+=(--write-auto-subs)
+else
+    args+=(--write-subs --write-auto-subs)
+fi
+
+if [ -n "$LANG_SPEC" ]; then
+    args+=(--sub-langs "$LANG_SPEC")
+else
+    args+=(--sub-langs best)
+fi
+
+case "$FMT" in
+    vtt) args+=(--sub-format vtt) ;;
+    txt) args+=(--sub-format srt) ;;
+    *)   args+=(--sub-format srt) ;;
+esac
+
+[ "$NO_PLAYLIST" -eq 1 ] && args+=(--no-playlist)
+
+args+=(-o "$OUT_TEMPLATE" "$URL")
+
+if [ "$DRY_RUN" -eq 1 ]; then
+    yt_echo_cmd "${args[@]:1}"
+    exit 0
+fi
+
+# ── Execute ───────────────────────────────────────────────────
+set +e
+out="$(mktemp)"
+err_tmp="$(mktemp)"
+"${args[@]}" >"$out" 2>"$err_tmp"
+rc=$?
+set -e
+
+if [ "$rc" -ne 0 ]; then
+    # Unavailable-subtitle detection: exit!=0 AND stderr matches no-subs patterns
+    if grep -qiE 'no subtitles|no captions|unable to extract|subtitles not available' "$err_tmp"; then
+        rm -f "$out" "$err_tmp"
+        err "unavailable subtitles for this video (try --list-subs to check)"
+    fi
+    # Re-surface the real yt-dlp error otherwise
+    sed 's/^/    /' "$err_tmp" >&2
+    rm -f "$out" "$err_tmp"
+    exit "$rc"
+fi
+rm -f "$out" "$err_tmp"
+
+# ── Post-conversion for txt format ────────────────────────────
+if [ "$FMT" = "txt" ]; then
+    search_dir="."
+    [ -n "$OUT_DIR" ] && search_dir="$OUT_DIR"
+    while IFS= read -r -d '' f; do
+        case "$f" in
+            *.srt) convert_srt_to_txt "$f" ;;
+        esac
+    done < <(find "$search_dir" -maxdepth 1 -name '*.srt' -print0 2>/dev/null || true)
+fi
@@ -0,0 +1,5 @@
+#!/usr/bin/env bash
+set -euo pipefail
+# POS: media yt-ytsync — Incrementally sync YouTube channels/playlists into ~/Videos
+# -h|--help forwarded via exec below
+exec pos media ytsync "$@"
@@ -11,10 +11,11 @@ _pos_flags[communication-telegram-sender]="--type --caption --parse-mode --no-pr
 _pos_flags[docker-stack]="-a --all"
 _pos_flags[docker-vbox]="--dir --gpu --device --port --cpus --memory --network"
 _pos_flags[entertainment-send]="--print --markdown"
-_pos_flags[media-grab]="--audio --video --best --worst --output --no-playlist --cookies --dry-run"
-_pos_flags[media-mp3]="--output --no-playlist --cookies --by-artist --dry-run"
-_pos_flags[media-mp4]="--format --best --worst --output --no-playlist --cookies --dry-run"
 _pos_flags[media-sync]="--mp3 --mp4 --source --dry-run"
+_pos_flags[media-yt-grab]="--audio --video --best --worst --output --no-playlist --cookies --dry-run"
+_pos_flags[media-yt-mp3]="--output --no-playlist --cookies --by-artist --dry-run"
+_pos_flags[media-yt-mp4]="--format --best --worst --output --no-playlist --cookies --dry-run"
+_pos_flags[media-yt-subtitles]="--lang --format --auto-only --output --list-subs --no-playlist --dry-run"
 _pos_flags[media-ytsync]="--dry-run"
 _pos_flags[network-checkport]="--tcp --udp --ping --no-banner --versions --timeout"
 _pos_flags[network-download]="--dir --out --split --seed --force --upload --gid --tmux"
@@ -42,6 +43,7 @@ _pos_subcmds[docker-compose]="ls installed up down restart logs update config me
 _pos_subcmds[docker-vbox]="create enter stop start rm ls menu"
 _pos_subcmds[media-sync]="menu"
 _pos_subcmds[media-ytsync]="add sync list remove"
+_pos_subcmds[media-yt]="mp3 mp4 grab ytsync subtitles"
 _pos_subcmds[network-download]="start stop status add torrent metalink list info files peers pause resume remove purge move limit set watch restart retry replace menu"
 _pos_subcmds[share-nfs-client]="mount unmount list persist unpersist menu"
 _pos_subcmds[share-nfs-server]="status share unshare list reload enable disable menu"
@@ -8,6 +8,7 @@
 # API keys (each provider needs its own):
 #   AI_GEMINI_API_KEY=<key>       # Gemini API key from aistudio.google.com
 #   OPENROUTER_API_KEY=<key>      # OpenRouter API key from openrouter.ai
+# Legacy fallback: AI_API_KEY=<key> is honored when the provider's own key is unset
 #
 # Model overrides (optional, defaults per provider):
 #   AI_GEMINI_MODEL=<model>       # Gemini model id (default: gemini-2.5-flash)
@@ -14,11 +14,26 @@ fi
 source "$(dirname "$0")/lib/common.sh"
 source "$(dirname "$0")/lib/flags.sh"

+# Return the current install.sh version (e.g. "0.0c174").
+# Derived from git commit count. Empty when .git is absent.
+# Override with INSTALL_VERSION_OVERRIDE for testing.
+install_version() {
+    if [ "${INSTALL_VERSION_OVERRIDE+x}" ]; then
+        printf '%s' "$INSTALL_VERSION_OVERRIDE"
+        return
+    fi
+    local repo_dir count
+    repo_dir="$(cd "$(dirname "$0")" && pwd)"
+    count="$(git -C "$repo_dir" rev-list --count HEAD 2>/dev/null)" || { printf ''; return; }
+    printf '0.0c%s' "$count"
+}
+
 # Exported so child phases (preinstall.sh, postinstall.sh) inherit it —
 # otherwise '--dry-run' silently executes them for real.
 export DRY_RUN=0
 RUN_APPS=0
 RUN_FEATURES=0
+FORCE=0
 SKIP_PHASES=""
 STEPS_SPEC=""

@@ -58,6 +73,7 @@ Options:
  --full            Core install + all optional apps (non-interactive)
  --feature         Install features/ scripts (prompts before overwriting)
  --dry-run         Show what would be done without executing
+  --force           Re-install even if the version matches
  --skip <phase>    Skip a phase (repeatable):
                      preinstall, scripts, postinstall, scalepoint, apps
  --steps <spec>    Run only specific phases. Format: 1,3,4 or 1-3
@@ -79,6 +95,7 @@ while [[ $# -gt 0 ]]; do
        --full) RUN_APPS=2; shift ;;
        --feature) RUN_FEATURES=1; shift ;;
        --dry-run) DRY_RUN=1; shift ;;
+        --force) FORCE=1; shift ;;
        --skip)
            [ -z "${2:-}" ] && err "Missing value for --skip"
            SKIP_PHASES="${SKIP_PHASES:+$SKIP_PHASES,}$2"
@@ -95,6 +112,24 @@ while [[ $# -gt 0 ]]; do
    esac
 done

+# ── Version gate ────────────────────────────────────────────────
+CURRENT_VERSION="$(install_version)"
+if [ "${FORCE:-0}" -ne 1 ] && [ -n "$CURRENT_VERSION" ]; then
+    INSTALLED_VERSION="$(flag_value installed_version 2>/dev/null)" || true
+    if [ -n "$INSTALLED_VERSION" ]; then
+        current_num="${CURRENT_VERSION#0.0c}"
+        installed_num="${INSTALLED_VERSION#0.0c}"
+        if [ "$current_num" -eq "$installed_num" ] 2>/dev/null; then
+            if [ "${DRY_RUN:-0}" -eq 1 ]; then
+                log "(dry-run) Would skip install: already at version $CURRENT_VERSION"
+            else
+                log "Already installed ($CURRENT_VERSION). Use --force to re-install."
+            fi
+            exit 0
+        fi
+    fi
+fi
+
 # ── Phase runner ────────────────────────────────────────────────
 # Phase names → numbers:  preinstall=1 scripts=2 postinstall=3 scalepoint=4
 should_run() {
@@ -248,6 +283,11 @@ echo "${GREEN}══════════════════════
 echo "${GREEN}  Bootstrap complete ($(timer_stop))${RESET}"
 echo "${GREEN}════════════════════════════════════════════${RESET}"

+# ── Record installed version ────────────────────────────────────
+if [ "${DRY_RUN:-0}" -ne 1 ] && [ -n "${CURRENT_VERSION:-}" ]; then
+    flag_set installed_version "$CURRENT_VERSION"
+fi
+
 # ── Optional apps ──────────────────────────────────────────────
 if [ "$RUN_APPS" -eq 1 ]; then
    echo
@@ -0,0 +1,50 @@
+# lib/yt-lib.sh — shared helpers for yt-dlp-based media tools.
+# Sourced opt-in by yt-* subcommand files. Uses err() from lib/common.sh.
+
+# yt_check_deps [dry_run] [ffmpeg_purpose]
+# Check yt-dlp (+ ffmpeg unless dry_run=1 and caller wants dry-run to skip deps).
+# ffmpeg_purpose is the parenthetical in the error message (default: "MP3 conversion").
+# ytsync overrides this deliberately (needs yt-dlp+jq even in dry-run).
+yt_check_deps() {
+    local dry="${1:-0}" purpose="${2:-MP3 conversion}"
+    command -v yt-dlp &>/dev/null || err "yt-dlp not found — install it with: sudo apt install yt-dlp"
+    if [ "$dry" -eq 0 ]; then
+        command -v ffmpeg &>/dev/null || err "ffmpeg not found (needed for $purpose) — install it with: sudo apt install ffmpeg"
+    fi
+}
+
+# yt_validate_url <url>
+# Returns 1 (does NOT exit) when URL doesn't start with http:// or https://;
+# prints the diagnostic to stderr. Callers surface the error themselves (e.g.
+# `yt_validate_url "$url" 2>/dev/null || err "…"` with their own prefix) so a
+# helper whose only job is to check can never kill the caller's error path.
+yt_validate_url() {
+    local url="$1"
+    case "$url" in
+        http://*|https://*) return 0 ;;
+        *) echo "not a valid URL: $url (must start with http:// or https://)" >&2; return 1 ;;
+    esac
+}
+
+# yt_echo_cmd <args...>
+# Prints the yt-dlp command for --dry-run mode
+yt_echo_cmd() {
+    echo "yt-dlp $*"
+}
+
+# classify_url <url>
+# Domain classification: music.youtube/soundcloud/bandcamp → audio;
+# youtube/youtu.be/vimeo/twitch → video; unknown → ${GRAB_DEFAULT:-video}
+# Migrated from bin/pos-media-grab
+classify_url() {
+    local url="$1" mode="${GRAB_DEFAULT:-video}"
+    case "$url" in
+        *music.youtube.com*)  echo "audio" ;;
+        *soundcloud.com*)     echo "audio" ;;
+        *bandcamp.com*)       echo "audio" ;;
+        *youtube.com*|*youtu.be*) echo "video" ;;
+        *vimeo.com*)          echo "video" ;;
+        *twitch.tv*)          echo "video" ;;
+        *)                    echo "$mode" ;;
+    esac
+}
@@ -42,6 +42,7 @@ silently.
 | --- | --- |
 | `t-ai-server-flags.sh` | `pos-ai-server` ExecStart flag set: defaults, CLI, config, dedupe, one-token-per-flag |
 | `t-ai-hf-download.sh` | `pos ai hf download` success + failure honesty (no `.hf-meta` on partial failure, rc != 0) |
+| `t-ai-key-resolution.sh` | `pos ai` API-key contract: provider key > legacy `AI_API_KEY` fallback > error; leakage guard, env-wins, providers status sync |
 | `t-ai-llama-detect.sh` | `pos ai-server status` version detection, "unknown", missing-binary failure |
 | `t-unsupported-flags.sh` | unsupported-option handling: CLI/config/env hard errors, dropped defaults, word-boundary match |
 | `t-systemd-unit.sh` | generated unit: one ExecStart, quoted paths, `systemd-analyze verify` |
@@ -52,4 +53,6 @@ silently.
 | `t-uninstall-manifest.sh` | install.sh ↔ POS_LIBS symmetry, user-unit discovery, marker-driven plugin removal |
 | `t-gen-docs-drift.sh` | `make gen` idempotence on a pristine tracked tree (CI drift gate) |
 | `t-lint-gate.sh` | `make lint` green on the real tree; planted violations are caught and named |
-| `t-share-mountpoint.sh` | share-client `ask_mountpoint` UX: existing/new/declined/rejected paths, confirm gate, mkdir side effects, non-TTY stdin contract, static `n`→`t` guards |
+| `t-install-version.sh` | install.sh version gate: match→skip, mismatch→proceed, --force bypass, dry-run variant, flag write, numeric comparison |
+| `t-share-mountpoint.sh` | share-client `ask_mountpoint` UX: existing/new/declined/rejected paths, confirm gate, mkdir side effects, non-TTY stdin contract, static `n`→`t` guards |
+| `t-pos-media-yt.sh` | unified `pos media yt` suite: dispatcher + forwarder resolution, shared yt-lib helpers, yt-mp3/mp4/grab/subtitles flags, dry-run deps, `YT_OUT_DIR` seam, `GRAB_DEFAULT` config, negative controls (unsafe-URL no-expansion, `--lang en,ar` single arg, txt timestamp-stripping) |
@@ -0,0 +1,128 @@
+#!/usr/bin/env bash
+set -euo pipefail
+# t-ai-key-resolution.sh — `pos ai` API-key resolution contract:
+#   provider-specific key (AI_GEMINI_API_KEY / OPENROUTER_API_KEY)
+#   > legacy shared AI_API_KEY fallback > error; llamacpp needs no key.
+#
+# Regression for the 7ae2e77 "per-provider keys" migration: AI_API_KEY must be
+# honored ONLY when the active provider's own key is empty (backward-compat for
+# howto-taught single-key configs) and must NEVER override a provider key
+# (cross-provider leakage guard). Also pins env-wins (exported env beats
+# ai.env) and `pos ai providers` agreeing with resolve_key().
+#
+# Seam: `pos ai models` with a curl stub on PATH that records -H headers to a
+# log and returns deterministic per-provider JSON (no sessions are written by
+# `models`, unlike ask/chat).
+
+run_test() {
+    require_cmd jq "pos ai key resolution" || return 0
+
+    local sandbox cfg home stubs curl_log
+    sandbox="$(mksandbox ai-key-resolution)"
+    cfg="$sandbox/cfg"
+    home="$sandbox/home"
+    stubs="$sandbox/stubs"
+    mkdir -p "$cfg" "$home" "$stubs"
+    curl_log="$sandbox/curl.log"
+    : > "$curl_log"
+    : > "$cfg/ai.env"
+
+    # curl stub: log every -H <header> pair; reply with provider-shaped JSON +
+    # the trailing \n%{http_code} line the adapters' --write-out expects.
+    cat > "$stubs/curl" <<STUB
+#!/usr/bin/env bash
+all="\$*"
+while [ \$# -gt 0 ]; do
+    case "\$1" in
+        -H) printf 'HDR %s\n' "\$2" >> "$curl_log"; shift 2 ;;
+        *) shift ;;
+    esac
+done
+case "\$all" in
+    *generativelanguage.googleapis.com*)
+        printf '%s\n200' '{"models":[{"name":"models/gemini-2.5-flash","supportedGenerationMethods":["generateContent"]}]}' ;;
+    *openrouter.ai*)
+        printf '%s\n200' '{"data":[{"id":"openrouter/auto"}]}' ;;
+    *)
+        printf '%s\n200' '{"data":[{"id":"loaded-model"}]}' ;;
+esac
+STUB
+    chmod +x "$stubs/curl"
+
+    local posai="$ROOT/bin/pos-ai"
+    # Hermetic env: `env -i` drops every inherited variable (incl. any ambient
+    # AI_*), so each case exercises exactly the values declared below.
+    local path_env=(-i PATH="$stubs:/usr/bin:/bin" CONFIG_FILE="$cfg/ai.env" HOME="$home")
+
+    # ── Case 1: gemini via provider key only ──
+    printf 'AI_GEMINI_API_KEY=GEMFILEKEY\n' > "$cfg/ai.env"
+    test_run_env "${path_env[@]}" -- "$posai" models
+    check_rc "C1 gemini via AI_GEMINI_API_KEY works" 0 "$TR_RC"
+    check_contains "C1 gemini header carries provider key" "x-goog-api-key: GEMFILEKEY" "$(cat "$curl_log")"
+
+    # ── Case 2: gemini via legacy AI_API_KEY only (core regression) ──
+    : > "$curl_log"
+    printf 'AI_API_KEY=AIKEYONLY\n' > "$cfg/ai.env"
+    test_run_env "${path_env[@]}" -- "$posai" models
+    check_rc "C2 gemini via legacy AI_API_KEY works" 0 "$TR_RC"
+    check_contains "C2 gemini header carries legacy key" "x-goog-api-key: AIKEYONLY" "$(cat "$curl_log")"
+
+    # ── Case 3: gemini with both → provider key wins (leakage guard) ──
+    : > "$curl_log"
+    printf 'AI_GEMINI_API_KEY=GEMWIN\nAI_API_KEY=AIKEYLOSE\n' > "$cfg/ai.env"
+    test_run_env "${path_env[@]}" -- "$posai" models
+    check_rc "C3 both set still works" 0 "$TR_RC"
+    check_contains "C3 provider key wins" "x-goog-api-key: GEMWIN" "$(cat "$curl_log")"
+    check_not_contains "C3 shared key not leaked" "AIKEYLOSE" "$(cat "$curl_log")"
+
+    # ── Case 4: openrouter via provider key only ──
+    : > "$curl_log"
+    printf 'OPENROUTER_API_KEY=ORFILEKEY\n' > "$cfg/ai.env"
+    test_run_env "${path_env[@]}" -- "$posai" --provider openrouter models
+    check_rc "C4 openrouter via OPENROUTER_API_KEY works" 0 "$TR_RC"
+    check_contains "C4 openrouter auth carries provider key" "Authorization: Bearer ORFILEKEY" "$(cat "$curl_log")"
+
+    # ── Case 5: openrouter via legacy AI_API_KEY only ──
+    : > "$curl_log"
+    printf 'AI_API_KEY=AIKEYONLY\n' > "$cfg/ai.env"
+    test_run_env "${path_env[@]}" -- "$posai" --provider openrouter models
+    check_rc "C5 openrouter via legacy AI_API_KEY works" 0 "$TR_RC"
+    check_contains "C5 openrouter auth carries legacy key" "Authorization: Bearer AIKEYONLY" "$(cat "$curl_log")"
+
+    # ── Case 6: openrouter with both → provider key wins ──
+    : > "$curl_log"
+    printf 'OPENROUTER_API_KEY=ORWIN\nAI_API_KEY=AIKEYLOSE\n' > "$cfg/ai.env"
+    test_run_env "${path_env[@]}" -- "$posai" --provider openrouter models
+    check_rc "C6 both set still works" 0 "$TR_RC"
+    check_contains "C6 openrouter provider key wins" "Authorization: Bearer ORWIN" "$(cat "$curl_log")"
+    check_not_contains "C6 shared key not leaked" "AIKEYLOSE" "$(cat "$curl_log")"
+
+    # ── Case 7: env-wins — exported provider key beats ai.env file value ──
+    : > "$curl_log"
+    printf 'AI_GEMINI_API_KEY=FILEVALUE\n' > "$cfg/ai.env"
+    test_run_env "${path_env[@]}" AI_GEMINI_API_KEY=ENVVALUE -- "$posai" models
+    check_rc "C7 env-wins run works" 0 "$TR_RC"
+    check_contains "C7 exported env key used" "x-goog-api-key: ENVVALUE" "$(cat "$curl_log")"
+    check_not_contains "C7 file value suppressed by env" "FILEVALUE" "$(cat "$curl_log")"
+
+    # ── Case 8: llamacpp needs no key ──
+    : > "$curl_log"
+    : > "$cfg/ai.env"
+    test_run_env "${path_env[@]}" -- "$posai" --provider llamacpp models
+    check_rc "C8 llamacpp works with no key" 0 "$TR_RC"
+    check_contains "C8 llamacpp lists models" "Local llama.cpp models:" "$TR_OUT"
+
+    # ── Case 9: missing key → rc 1 + byte-stable message ──
+    test_run_env "${path_env[@]}" -- "$posai" models
+    check_rc "C9 missing key exits nonzero" 1 "$TR_RC"
+    check_contains "C9 stable error message" "No Gemini API key — run 'pos config ai' and set AI_GEMINI_API_KEY" "$TR_OUT"
+
+    # ── Case 10: providers status agrees with resolve_key (AI_API_KEY only) ──
+    local prov
+    printf 'AI_API_KEY=SHAREDKEY\n' > "$cfg/ai.env"
+    test_run_env "${path_env[@]}" -- "$posai" providers
+    prov="$(printf '%s\n' "$TR_OUT" | grep configured || true)"
+    check_contains "C10 gemini row shows configured" "gemini" "$prov"
+    check_contains "C10 openrouter row shows configured" "openrouter" "$prov"
+    check_not_contains "C10 no 'not configured' row" "not configured" "$TR_OUT"
+}
@@ -201,7 +201,7 @@ STUB
    for tool in pos-ai pos-ai-hf pos-ai-server pos-communication-matrix-listener \
                 pos-communication-matrix-sender pos-communication-scrcpy \
                 pos-communication-telegram-listener pos-communication-telegram-sender \
-                 pos-media-grab pos-network-download; do
+                 pos-media-yt-grab pos-network-download; do
        if grep -q "load_env_file" "$ROOT/bin/$tool"; then
            printf '  PASS  %s uses shared load_env_file\n' "$tool"
        else
@@ -0,0 +1,174 @@
+#!/usr/bin/env bash
+set -euo pipefail
+# t-install-version.sh — install.sh version gate contract:
+#   match→skip with "Already installed", mismatch→proceed, --force bypass,
+#   no-git (empty) skip, dry-run variant, flag write after run,
+#   numeric comparison correctness (0.0c10 > 0.0c9).
+#
+# Seam: INSTALL_VERSION_OVERRIDE env var (presence check → empty = no-git path),
+# FLAGS_DIR env var (existing flag store seam).
+#
+# Proceed-path cases (2/3/4/5/8) use --skip all phases instead of --dry-run
+# because postinstall.sh is not fully dry-run safe (cat on non-existent file
+# after dry-run copy). Skipping all phases is functionally equivalent — the
+# gate fires before phases, and the banner + flag write still execute.
+
+run_test() {
+    local sandbox stubs flags_dir install_sh
+
+    sandbox="$(mksandbox install-version)"
+    stubs="$sandbox/stubs"
+    flags_dir="$sandbox/flags"
+    mkdir -p "$stubs" "$flags_dir"
+
+    install_sh="$ROOT/install.sh"
+
+    # sudo stub: just exec its arguments (bypasses real sudo in sandbox)
+    cat > "$stubs/sudo" <<'STUB'
+#!/usr/bin/env bash
+exec "$@"
+STUB
+    chmod +x "$stubs/sudo"
+
+    # install stub: delegate to the real install binary (needed so -d/-m flags
+    # work; we only shadow 'sudo' to avoid needing a tty/password)
+    cat > "$stubs/install" <<'STUB'
+#!/usr/bin/env bash
+exec /usr/bin/install "$@"
+STUB
+    chmod +x "$stubs/install"
+
+    # mkdir stub: just exec its arguments
+    cat > "$stubs/mkdir" <<'STUB'
+#!/usr/bin/env bash
+exec "$@"
+STUB
+    chmod +x "$stubs/mkdir"
+
+    local base_env=(PATH="$stubs:/usr/bin:/bin"
+        HOME="$sandbox/home"
+        FLAGS_DIR="$flags_dir")
+
+    # Helper: run install.sh with env overrides and capture output+rc.
+    run_install() {
+        local envs=() args=()
+        while [ $# -gt 0 ]; do
+            if [ "$1" = "--" ]; then shift; break; fi
+            envs+=("$1"); shift
+        done
+        args=("$@")
+        set +e
+        TR_OUT="$(env "${base_env[@]}" "${envs[@]}" bash "$install_sh" "${args[@]}" 2>&1)"
+        TR_RC=$?
+        set -e
+    }
+
+    # Helper: set a flag value directly (for pre-seeding installed_version)
+    set_flag() {
+        local name="$1" value="$2"
+        mkdir -p "$flags_dir"
+        printf '%s' "$value" > "$flags_dir/$name"
+    }
+
+    # Helper: read a flag value
+    get_flag() {
+        local name="$1"
+        local f="$flags_dir/$name"
+        [ -f "$f" ] && cat "$f" || printf ''
+    }
+
+    # ═══════════════════════════════════════════════════════════════
+    # Case 1: Match → skip ("Already installed")
+    #   Gate exits BEFORE any phase — safe without --dry-run or --skip.
+    # ═══════════════════════════════════════════════════════════════
+    set_flag "installed_version" "0.0c10"
+    run_install INSTALL_VERSION_OVERRIDE=0.0c10
+    check_rc "C1 match→skip exit code" 0 "$TR_RC"
+    check_contains "C1 match→skip message" "Already installed (0.0c10)" "$TR_OUT"
+
+    # ═══════════════════════════════════════════════════════════════
+    # Case 2: Mismatch → proceed (gate doesn't match, phases skipped)
+    # ═══════════════════════════════════════════════════════════════
+    rm -f "$flags_dir/installed_version"
+    set_flag "installed_version" "0.0c10"
+    run_install INSTALL_VERSION_OVERRIDE=0.0c11 -- --skip preinstall,scripts,postinstall,scalepoint
+    check_rc "C2 mismatch→proceed exit code" 0 "$TR_RC"
+    check_not_contains "C2 mismatch does not skip" "Already installed" "$TR_OUT"
+
+    # ═══════════════════════════════════════════════════════════════
+    # Case 3: Force bypasses match
+    # ═══════════════════════════════════════════════════════════════
+    rm -f "$flags_dir/installed_version"
+    set_flag "installed_version" "0.0c10"
+    run_install INSTALL_VERSION_OVERRIDE=0.0c10 -- --skip preinstall,scripts,postinstall,scalepoint --force
+    check_rc "C3 force bypasses exit code" 0 "$TR_RC"
+    check_not_contains "C3 force bypasses skip" "Already installed" "$TR_OUT"
+
+    # ═══════════════════════════════════════════════════════════════
+    # Case 4: No git (empty version via presence check)
+    #   INSTALL_VERSION_OVERRIDE="" with ${var+x} → empty → gate skipped
+    # ═══════════════════════════════════════════════════════════════
+    rm -f "$flags_dir/installed_version"
+    set_flag "installed_version" "0.0c10"
+    run_install INSTALL_VERSION_OVERRIDE="" -- --skip preinstall,scripts,postinstall,scalepoint
+    check_rc "C4 empty override→proceeds exit code" 0 "$TR_RC"
+    check_not_contains "C4 empty override does not skip" "Already installed" "$TR_OUT"
+
+    # ═══════════════════════════════════════════════════════════════
+    # Case 5: No installed flag → gate doesn't block
+    # ═══════════════════════════════════════════════════════════════
+    rm -f "$flags_dir/installed_version"
+    run_install INSTALL_VERSION_OVERRIDE=0.0c10 -- --skip preinstall,scripts,postinstall,scalepoint
+    check_rc "C5 no flag→proceeds exit code" 0 "$TR_RC"
+    check_not_contains "C5 no flag does not skip" "Already installed" "$TR_OUT"
+
+    # ═══════════════════════════════════════════════════════════════
+    # Case 6: Dry-run + match → "Would skip" (not "Already installed")
+    # ═══════════════════════════════════════════════════════════════
+    rm -f "$flags_dir/installed_version"
+    set_flag "installed_version" "0.0c10"
+    run_install INSTALL_VERSION_OVERRIDE=0.0c10 -- --dry-run
+    check_rc "C6 dry-run match exit code" 0 "$TR_RC"
+    check_contains "C6 dry-run shows Would skip" "Would skip install" "$TR_OUT"
+    check_not_contains "C6 dry-run not Already installed" "Already installed" "$TR_OUT"
+
+    # ═══════════════════════════════════════════════════════════════
+    # Case 7: Flag written after successful run
+    #   All phases skipped; sudo/install/mkdir stubs on PATH so
+    #   flag_set's `run sudo install` actually creates the flag file.
+    # ═══════════════════════════════════════════════════════════════
+    rm -f "$flags_dir/installed_version"
+    set_flag "installed_version" "0.0c10"
+    run_install INSTALL_VERSION_OVERRIDE=0.0c11 -- --skip preinstall,scripts,postinstall,scalepoint
+    check_rc "C7 all-skip exit code" 0 "$TR_RC"
+    local flag_val
+    flag_val="$(get_flag installed_version)"
+    check_eq "C7 flag written with current version" "0.0c11" "$flag_val"
+
+    # ═══════════════════════════════════════════════════════════════
+    # Case 8: Numeric comparison — 0.0c10 > 0.0c9 (not blocked)
+    # ═══════════════════════════════════════════════════════════════
+    rm -f "$flags_dir/installed_version"
+    set_flag "installed_version" "0.0c9"
+    run_install INSTALL_VERSION_OVERRIDE=0.0c10 -- --skip preinstall,scripts,postinstall,scalepoint
+    check_rc "C8 numeric 10>9 proceeds exit code" 0 "$TR_RC"
+    check_not_contains "C8 numeric 10>9 does not skip" "Already installed" "$TR_OUT"
+
+    # Also test: 0.0c9 with installed 0.0c10 → NOT a match
+    rm -f "$flags_dir/installed_version"
+    set_flag "installed_version" "0.0c10"
+    run_install INSTALL_VERSION_OVERRIDE=0.0c9 -- --skip preinstall,scripts,postinstall,scalepoint
+    check_rc "C8 numeric 9≠10 proceeds exit code" 0 "$TR_RC"
+    check_not_contains "C8 numeric 9≠10 does not skip" "Already installed" "$TR_OUT"
+
+    # ═══════════════════════════════════════════════════════════════
+    # Case 9: Force + match → still writes flag
+    # ═══════════════════════════════════════════════════════════════
+    rm -f "$flags_dir/installed_version"
+    set_flag "installed_version" "0.0c10"
+    run_install INSTALL_VERSION_OVERRIDE=0.0c10 -- --skip preinstall,scripts,postinstall,scalepoint --force
+    check_rc "C9 force+match exit code" 0 "$TR_RC"
+    local flag_val9
+    flag_val9="$(get_flag installed_version)"
+    check_eq "C9 force writes flag" "0.0c10" "$flag_val9"
+}
@@ -0,0 +1,279 @@
+#!/usr/bin/env bash
+set -euo pipefail
+# t-pos-media-yt.sh — POS--9 verification for the unified `pos media yt`
+# suite and its forwarders.
+#
+#   Part 1: dispatcher + forwarder resolution (bin/pos-media-yt, pos-media-mp3/
+#           mp4/grab forwarders, full chain through bin/pos)
+#   Part 2: lib/yt-lib.sh shared helpers (deps, url validation, classify)
+#   Part 3: yt-mp3 behaviors (flags, dry-run, YT_OUT_DIR seam, unsafe-URL guard)
+#   Part 4: yt-mp4 behaviors (format select flags, mutual exclusions, seam)
+#   Part 5: yt-grab classification + delegation (dry-run command strings) + config
+#   Part 6: yt-subtitles (defaults, --lang en,ar single-arg, formats),
+#           txt conversion (timestamps stripped), unavailable-subs detection
+#   Part 7: negative controls mandated by the Architect contract
+
+run_test() {
+    local sandbox stubs cfg
+    sandbox="$(mksandbox media-yt)"
+    stubs="$sandbox/stubs"
+    cfg="$sandbox/cfg"
+    mkdir -p "$stubs" "$cfg"
+
+    local ytdlp_log="$sandbox/ytdlp.log"
+    : > "$ytdlp_log"
+    # fake yt-dlp logs its exact argv (one per line) — lets us assert arg
+    # counting / no-expansion WITHOUT any network or real binary.
+    cat > "$stubs/yt-dlp" <<STUB
+#!/usr/bin/env bash
+printf 'yt-dlp %s\\n' "\$*" >> "$ytdlp_log"
+STUB
+    # ffmpeg stub: satisfies the non-dry-run deps guard; not actually used.
+    printf '#!/usr/bin/env bash\nexit 0\n' > "$stubs/ffmpeg"
+    chmod +x "$stubs/yt-dlp" "$stubs/ffmpeg"
+
+    local RB="$ROOT/bin"
+    local yt ytd="$RB/pos-media-yt" mp3="$RB/pos-media-yt-mp3" \
+          mp4="$RB/pos-media-yt-mp4" grab="$RB/pos-media-yt-grab" \
+          subs="$RB/pos-media-yt-subtitles"
+    local env_base=(PATH="$stubs:$RB:/usr/bin:/bin" CONFIG_DIR="$cfg" \
+                    YT_OUT_DIR="$sandbox/out")
+
+    # ═══ Part 1: dispatcher + forwarders ═══
+    # 1.0 bare dispatcher → usage listing subcommands (exit 0)
+    test_run_env "${env_base[@]}" -- "$ytd"
+    check_rc "dispatcher bare invocation = usage exit 0" 0 "$TR_RC"
+    check_contains "dispatcher usage lists mp3" "mp3" "$TR_OUT"
+    check_contains "dispatcher usage lists subtitles" "subtitles" "$TR_OUT"
+
+    # 1.1 dispatcher unknown subcommand → hard error, nonzero
+    test_run_env "${env_base[@]}" -- "$ytd" bogus
+    [ "$TR_RC" -ne 0 ] && printf '  PASS  dispatcher unknown subcommand exits nonzero\n' \
+                       || printf '  FAIL  dispatcher unknown subcommand exited 0\n'
+    check_contains "dispatcher unknown subcommand message" "unknown yt command" "$TR_OUT"
+
+    # 1.2 forwarder helpers: --help passes through to the real yt usage
+    test_run_env "${env_base[@]}" -- "$RB/pos-media-mp3" --help
+    check_rc "pos media mp3 --help forwards cleanly" 0 "$TR_RC"
+    check_contains "mp3 forwarder shows yt-mp3 usage" "pos media yt mp3 [options]" "$TR_OUT"
+
+    test_run_env "${env_base[@]}" -- "$RB/pos-media-mp4" --help
+    check_rc "pos media mp4 --help forwards cleanly" 0 "$TR_RC"
+    check_contains "mp4 forwarder shows yt-mp4 usage" "pos media yt mp4 [options]" "$TR_OUT"
+
+    test_run_env "${env_base[@]}" -- "$RB/pos-media-grab" --help
+    check_rc "pos media grab --help forwards cleanly" 0 "$TR_RC"
+    check_contains "grab forwarder shows yt-grab usage" "pos media yt grab [options]" "$TR_OUT"
+
+    # 1.3 ytsync forwarder --help forwards to pos media ytsync
+    test_run_env "${env_base[@]}" -- "$RB/pos-media-yt-ytsync" --help
+    check_contains "ytsync forwarder references media ytsync" "media ytsync" "$TR_OUT"
+
+    # 1.4 full dispatch chain: `pos media mp3 <url>` → yt-mp3 (fake yt-dlp called).
+    #    `media-yt-mp3` is non-interactive so bin/pos execs it without a tee.
+    : > "$ytdlp_log"
+    test_run_env "${env_base[@]}" -- "$RB/pos" media mp3 "http://example.com/x"
+    check_rc "chain pos media mp3 <url> resolves" 0 "$TR_RC"
+    check_contains "chain reaches yt-dlp with -x (audio path)" "-x" "$(cat "$ytdlp_log")"
+
+    # ═══ Part 2: lib/yt-lib.sh helpers ═══
+    source "$ROOT/lib/common.sh"
+    source "$ROOT/lib/yt-lib.sh"
+    # 2.0 yt_validate_url accepts http(s), rejects junk
+    yt_validate_url "https://youtube.com/watch?v=x" && printf '  PASS  url valid http/https accepted\n' \
+                       || printf '  FAIL  valid https url rejected\n'
+    test_run yt_validate_url "ftp://bad"
+    [ "$TR_RC" -ne 0 ] && printf '  PASS  invalid url rejected\n' || printf '  FAIL  invalid url accepted\n'
+    check_contains "invalid url error message" "not a valid URL" "$TR_OUT"
+
+    # 2.1 classify_url: audio / video / unknown-with-GRAB_DEFAULT
+    check_eq "music.youtube → audio" "audio" "$(classify_url "https://music.youtube.com/watch?v=x")"
+    check_eq "soundcloud → audio" "audio" "$(classify_url "https://soundcloud.com/a/b")"
+    check_eq "youtube.com → video" "video" "$(classify_url "https://youtube.com/watch?v=x")"
+    check_eq "vimeo → video" "video" "$(classify_url "https://vimeo.com/123")"
+    check_eq "unknown → default video" "video" "$(classify_url "https://example.com/x")"
+    check_eq "unknown → GRAB_DEFAULT=audio" "audio" "$(GRAB_DEFAULT=audio classify_url "https://example.com/x")"
+
+    # ═══ Part 3: yt-mp3 ═══
+    # 3.0 dry-run requires no deps and prints the yt-dlp command (audio flags)
+    test_run_env "${env_base[@]}" -- "$mp3" --dry-run "https://youtube.com/watch?v=dQw4w9WgXcQ"
+    check_rc "mp3 dry-run ok" 0 "$TR_RC"
+    check_contains "mp3 dry-run has -x --audio-format mp3" "--audio-format mp3" "$TR_OUT"
+    check_contains "mp3 dry-run has --embed-metadata" "--embed-metadata" "$TR_OUT"
+
+    # 3.1 --by-artist template
+    test_run_env "${env_base[@]}" -- "$mp3" --dry-run --by-artist "https://youtu.be/x"
+    check_contains "mp3 --by-artist organizes by artist/uploader" "%(artist,uploader)s/" "$TR_OUT"
+
+    # 3.2 --no-playlist propagated
+    test_run_env "${env_base[@]}" -- "$mp3" --dry-run --no-playlist "https://youtube.com/watch?v=x"
+    check_contains "mp3 --no-playlist passed through" "--no-playlist" "$TR_OUT"
+
+    # 3.3 --cookies must exist
+    test_run_env "${env_base[@]}" -- "$mp3" --dry-run --cookies "$sandbox/nope.txt" "https://youtube.com/watch?v=x"
+    [ "$TR_RC" -ne 0 ] && printf '  PASS  mp3 missing cookies file errors\n' \
+                       || printf '  FAIL  mp3 accepted missing cookies file\n'
+
+    # 3.4 YT_OUT_DIR seam overrides default output
+    test_run_env "${env_base[@]}" -- "$mp3" --dry-run "https://youtube.com/watch?v=x"
+    check_contains "mp3 uses YT_OUT_DIR seam" "$sandbox/out/%(title)s.%(ext)s" "$TR_OUT"
+
+    # 3.5 missing dep in non-dry-run → hard error (no yt-dlp on PATH at all)
+    test_run_env PATH="/usr/bin:/bin" -- "$mp3" "https://youtube.com/watch?v=x"
+    [ "$TR_RC" -ne 0 ] && printf '  PASS  mp3 without yt-dlp in path errors\n' \
+                       || printf '  FAIL  mp3 ran without yt-dlp present\n'
+
+    # 3.6 no URL → usage exit 0
+    test_run_env "${env_base[@]}" -- "$mp3" --dry-run
+    check_rc "mp3 no URL → usage exit 0" 0 "$TR_RC"
+    check_contains "mp3 no URL prints usage" "Usage: pos media yt mp3" "$TR_OUT"
+
+    # 3.7 NEGATIVE CONTROL: unsafe URL not expanded — passed as ONE literal arg.
+    #    `$(echo pwned)` stays literal inside the URL token; no second pwned word
+    #    appears in the argv log (which would mean command substitution ran).
+    : > "$ytdlp_log"
+    bad='$(echo pwned)'
+    test_run_env "${env_base[@]}" -- "$mp3" "http://example.com/$bad"
+    check_rc "unsafe URL run (fake yt-dlp) ok" 0 "$TR_RC"
+    local logged; logged="$(cat "$ytdlp_log")"
+    check_contains "url passed literally (single arg)" "\$(echo pwned)" "$logged"
+    check_not_contains "no separate pwned word from substitution" "example.com/  pwned" "$logged"
+
+    # ═══ Part 4: yt-mp4 ═══
+    # 4.0 --best
+    test_run_env "${env_base[@]}" -- "$mp4" --dry-run --best "https://youtube.com/watch?v=x"
+    check_contains "mp4 --best selects bestvideo+bestaudio" "bestvideo*+bestaudio/best" "$TR_OUT"
+
+    # 4.1 --worst
+    test_run_env "${env_base[@]}" -- "$mp4" --dry-run --worst "https://youtube.com/watch?v=x"
+    check_contains "mp4 --worst selects worst" "-f worst" "$TR_OUT"
+
+    # 4.2 -f id skips prompt
+    test_run_env "${env_base[@]}" -- "$mp4" --dry-run -f 22 "https://youtube.com/watch?v=x"
+    check_contains "mp4 -f 22 (no prompt)" "-f 22" "$TR_OUT"
+
+    # 4.3 mutual exclusions
+    test_run_env "${env_base[@]}" -- "$mp4" --dry-run --best --worst "https://youtube.com/watch?v=x"
+    [ "$TR_RC" -ne 0 ] && printf '  PASS  mp4 --best/--worst mutually exclusive\n' \
+                       || printf '  FAIL  mp4 allowed --best and --worst together\n'
+    test_run_env "${env_base[@]}" -- "$mp4" --dry-run -f 22 --best "https://youtube.com/watch?v=x"
+    [ "$TR_RC" -ne 0 ] && printf '  PASS  mp4 --format/--best mutually exclusive\n' \
+                       || printf '  FAIL  mp4 allowed --format and --best together\n'
+
+    # 4.4 YT_OUT_DIR seam
+    test_run_env "${env_base[@]}" -- "$mp4" --dry-run --best "https://youtube.com/watch?v=x"
+    check_contains "mp4 uses YT_OUT_DIR seam" "$sandbox/out/%(title)s.%(ext)s" "$TR_OUT"
+
+    # 4.5 no URL → usage
+    test_run_env "${env_base[@]}" -- "$mp4" --dry-run --best
+    check_rc "mp4 no URL → usage exit 0" 0 "$TR_RC"
+    check_contains "mp4 no URL prints usage" "Usage: pos media yt mp4" "$TR_OUT"
+
+    # ═══ Part 5: yt-grab classification + delegation (dry-run) + config ═══
+    # 5.0 music.youtube → audio route (dry-run prints delegate command, no exec)
+    test_run_env "${env_base[@]}" -- "$grab" --dry-run "https://music.youtube.com/watch?v=abc"
+    check_contains "grab music.youtube routes to yt mp3" "pos media yt mp3" "$TR_OUT"
+    check_not_contains "grab music.youtube not routed to mp4" "pos media yt mp4" "$TR_OUT"
+
+    # 5.1 youtube.com → video route (default --best)
+    test_run_env "${env_base[@]}" -- "$grab" --dry-run "https://youtube.com/watch?v=xyz"
+    check_contains "grab youtube routes to yt mp4" "pos media yt mp4 --best" "$TR_OUT"
+
+    # 5.2 --audio forces audio despite video domain
+    test_run_env "${env_base[@]}" -- "$grab" --dry-run --audio "https://youtube.com/watch?v=abc"
+    check_contains "grab --audio forces yt mp3" "pos media yt mp3" "$TR_OUT"
+
+    # 5.3 --worst → video --worst
+    test_run_env "${env_base[@]}" -- "$grab" --dry-run --worst "https://youtube.com/watch?v=abc"
+    check_contains "grab --worst routes to mp4 --worst" "pos media yt mp4 --worst" "$TR_OUT"
+
+    # 5.4 --audio + --video mutually exclusive
+    test_run_env "${env_base[@]}" -- "$grab" --dry-run --audio --video "https://youtube.com/watch?v=abc"
+    [ "$TR_RC" -ne 0 ] && printf '  PASS  grab --audio/--video mutually exclusive\n' \
+                       || printf '  FAIL  grab allowed --audio and --video together\n'
+
+    # 5.5 invalid URL
+    test_run_env "${env_base[@]}" -- "$grab" "not-a-url"
+    [ "$TR_RC" -ne 0 ] && printf '  PASS  grab rejects invalid url\n' \
+                       || printf '  FAIL  grab accepted invalid url\n'
+    check_contains "grab error prefixed yt-grab" "yt-grab:" "$TR_OUT"
+
+    # 5.6 unknown domain honors GRAB_DEFAULT via config file (audio)
+    printf 'GRAB_DEFAULT=audio\n' > "$cfg/grab.env"
+    test_run_env "${env_base[@]}" -- "$grab" --dry-run "https://example.com/x"
+    check_contains "grab unknown domain honors GRAB_DEFAULT=audio" "pos media yt mp3" "$TR_OUT"
+
+    # ═══ Part 6: yt-subtitles ═══
+    # 6.0 defaults: --write-subs --write-auto-subs --sub-langs best
+    test_run_env "${env_base[@]}" -- "$subs" --dry-run "https://youtube.com/watch?v=x"
+    check_contains "subs default writes manual subs" "--write-subs" "$TR_OUT"
+    check_contains "subs default writes auto subs" "--write-auto-subs" "$TR_OUT"
+    check_contains "subs default sub-langs best" "--sub-langs best" "$TR_OUT"
+
+    # 6.1 NEGATIVE CONTROL: --lang en,ar becomes ONE --sub-langs arg
+    test_run_env "${env_base[@]}" -- "$subs" --dry-run --lang en,ar "https://youtube.com/watch?v=x"
+    check_contains "subs --lang en,ar single arg" "--sub-langs en,ar" "$TR_OUT"
+    check_not_contains "subs does not split --lang (no single 'en')" "--sub-langs en " "$TR_OUT"
+
+    # 6.2 --format vtt
+    test_run_env "${env_base[@]}" -- "$subs" --dry-run --format vtt "https://youtube.com/watch?v=x"
+    check_contains "subs --format vtt" "--sub-format vtt" "$TR_OUT"
+
+    # 6.3 --auto-only drops --write-subs
+    test_run_env "${env_base[@]}" -- "$subs" --dry-run --auto-only "https://youtube.com/watch?v=x"
+    check_not_contains "subs --auto-only drops manual subs" "--write-subs" "$TR_OUT"
+    check_contains "subs --auto-only keeps auto subs" "--write-auto-subs" "$TR_OUT"
+
+    # 6.4 --output dir template
+    test_run_env "${env_base[@]}" -- "$subs" --dry-run --output "$sandbox/subs" "https://youtube.com/watch?v=x"
+    check_contains "subs --output template" "$sandbox/subs/%(title)s.%(sub_lang)s.%(ext)s" "$TR_OUT"
+
+    # 6.5 invalid --format
+    test_run_env "${env_base[@]}" -- "$subs" --dry-run --format bogus "https://youtube.com/watch?v=x"
+    [ "$TR_RC" -ne 0 ] && printf '  PASS  subs rejects unknown format\n' \
+                       || printf '  FAIL  subs accepted unknown format\n'
+
+    # 6.6 unavailable subs: fake yt-dlp fails with no-subtitle stderr → friendly error
+    mkdir -p "$stubs/subsfail"
+    cat > "$stubs/subsfail/yt-dlp" <<STUB
+#!/usr/bin/env bash
+printf 'ERROR: no subtitles found' >&2
+exit 1
+STUB
+    chmod +x "$stubs/subsfail/yt-dlp"
+    test_run_env PATH="$stubs/subsfail:/usr/bin:/bin" -- "$subs" "https://youtube.com/watch?v=x"
+    [ "$TR_RC" -ne 0 ] && printf '  PASS  subs no-subtitles exits nonzero\n' \
+                       || printf '  FAIL  subs no-subtitles exited 0\n'
+    check_contains "subs unavailable-subs message" "unavailable subtitles" "$TR_OUT"
+
+    # 6.7 NEGATIVE CONTROL: txt conversion strips SRT timestamps — run the real
+#    tool non-dry with a fake yt-dlp that writes an .srt into the cwd; the txt
+#    converter must strip timestamps/html and keep the words.
+    local txtdir="$sandbox/txtdir"
+    mkdir -p "$txtdir" "$stubs/txtsubs"
+    cat > "$stubs/txtsubs/yt-dlp" <<STUB
+#!/usr/bin/env bash
+printf '1\\n00:00:01,000 --> 00:00:02,000\\nHello <i>world</i>\\n\\n2\\n00:00:03,000 --> 00:00:04,000\\nSecond line\\n' > foo.srt
+exit 0
+STUB
+    chmod +x "$stubs/txtsubs/yt-dlp"
+    (
+        cd "$txtdir"
+        env PATH="$stubs/txtsubs:/usr/bin:/bin" "$subs" --format txt "https://youtube.com/watch?v=x"
+    ) >"$sandbox/txtrun.log" 2>&1
+    local txt; txt="$(cat "$txtdir/foo.txt" 2>/dev/null || true)"
+    check_not_contains "txt output strips timestamps" "-->" "$txt"
+    check_not_contains "txt output strips html tags" "<i>" "$txt"
+    check_contains "txt output keeps words" "Hello world" "$txt"
+
+    # 6.8 subs dry-run skips deps (yt-dlp not in path) — needs no binaries
+    test_run_env PATH="/usr/bin:/bin" -- "$subs" --dry-run "https://youtube.com/watch?v=x"
+    check_rc "subs dry-run works without yt-dlp (skips deps)" 0 "$TR_RC"
+    check_contains "subs dry-run prints yt-dlp cmd" "yt-dlp" "$TR_OUT"
+
+    # 6.9 subs no URL → error (not usage), exit 1
+    test_run_env "${env_base[@]}" -- "$subs" --dry-run
+    [ "$TR_RC" -ne 0 ] && printf '  PASS  subs no URL exits nonzero\n' \
+                       || printf '  FAIL  subs no URL exited 0\n'
+    check_contains "subs no URL error message" "missing URL (see --help)" "$TR_OUT"
+}