Report which exit is which, instead of one ambiguous "public IP"

`status` probed https://1.1.1.1/cdn-cgi/trace and printed the answer as
"public IP". In test mode 1.1.1.1 is the *only* address routed into the tunnel,
so that line reported a PIA exit while every other packet left directly — a
test tunnel reading exactly like a full one.

Found on a live container: default route still via eth0, one 1.1.1.1/32 route
through pia0, and the old status line claiming a PIA public IP. This is a
plausible route to concluding the VPN is on when it is not, which is close to
the confusion this skill exists to prevent.

Status now names the mode and, in test mode, prints both exits with the real
address called out. 1.0.0.1 serves the same trace endpoint as 1.1.1.1 and is
never routed into the tunnel, so the direct exit can be probed without DNS.

Verified against all four states: no tunnel, test mode on a live tunnel that
was already up, full tunnel, and after teardown.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

CLAUDE.md

@@ -203,8 +203,7 @@ docker exec stdout → tokio task → emit("terminal-output-{sessionId}") → li
 ### Container (`container/`)
 
 - **`Dockerfile`** — Ubuntu 24.04 base with Claude Code, Node.js 22, Python 3.12, Rust, Docker CLI, git, gh, AWS CLI v2, ripgrep, pnpm, uv, ruff pre-installed, plus the shared
-  libraries a browser links against (see below) and the VPN tooling the `vpn_support_enabled`
-  toggle grants capability for (`iproute2`, `wireguard-tools`, `iptables`)
+  libraries a browser links against (see below)
 - **Browser runtime libraries are baked in; browser *binaries* are not.** A layer runs
   `npx --yes playwright@latest install-deps chromium` as root, so Playwright names its own
   dependencies and the list cannot rot against Ubuntu 24.04's `t64` renames or a new Chromium
@@ -317,29 +316,17 @@ container is created once by a very long function where a dropped capability is
   base-image migration — leaving a project holding the capability with nothing able to exercise it,
   and no error that points at why. `iptables` is deliberately absent; see the Dockerfile comment.
 - **Anything built on this fails open.** The network namespace is rebuilt on every start and no
-  service manager runs inside, so a tunnel never survives stop/start or recreation — while leftover
-  `/run` state makes it look as though it did. Note the two different mechanisms: `/run` is in the
-  writable layer, so on a stop/start it is simply the same container's files, and on a recreation
-  `docker commit` has carried it into the snapshot. Traffic silently reverts to the real address.
-  Any future autostart or killswitch work starts here.
-- **`/run` riding the snapshot means a VPN client's key material can end up in an image.** Verified:
-  a fresh container off the whp snapshot already contained the `wg.priv` a previous tunnel left in
-  `/run`. Anything writing key material there inherits the problem — the same `docker commit`
-  hazard as `triple-c.git-token-hash` and the custom-env fingerprint, in a directory that looks
-  ephemeral and is not. A VPN client that does this should delete its key on teardown.
-- **`iptables` is baked, and picking `nftables` instead would have been wrong.** `Recommends:
-  nftables | iptables` is stripped by `--no-install-recommends`, and `wg-quick` needs a backend for
-  any `AllowedIPs = 0.0.0.0/0`. `nftables` is the tempting choice — preferred by `wg-quick`, half
-  the size — but `wg-quick` picks nft *unconditionally* when present, and its nft ruleset needs
-  `nft_fib_ipv4`, which LinuxKit (Docker Desktop for Mac) does not build while it *does* build
-  `xt_CONNMARK`. Shipping nftables would therefore have forfeited Mac. See the Dockerfile comment;
-  the kernel-config evidence is quoted there.
-- **Two `wg-quick` failures remain, and only one is ours to fix.** Full tunnels still need
-  `xt_CONNMARK`, which WSL2 before 6.6 lacks — nothing installable changes that. And every
-  provider's stock config carries a `DNS =` line that fails in `set_dns()` before any routing, so it
-  breaks split tunnels too; `openresolv` has no candidate on noble and `resolvconf` drags in
-  systemd-resolved, so that one is documented rather than fixed. Driving `wg` and `ip route`
-  directly avoids both, which is what the skill does.
+  service manager runs inside, so a tunnel never survives stop/start or recreation while `/run`
+  state persists through the snapshot and makes it look as though it did. Traffic silently reverts
+  to the real address. Any future autostart or killswitch work starts here.
+- **The `pia-vpn` skill is installed *and removed* from `VPN_SUPPORT_ENABLED`.** `container/skills/`
+  is baked to `/opt/triple-c-skills` and `install_feature_skill()` in `entrypoint.sh` copies it into
+  `~/.claude/skills/` on every start — refreshed each time, so a fix reaches existing projects, and
+  `rm -rf`'d first, so files dropped from a later version do not linger. The removal branch matters
+  as much as the install: `~/.claude` is a persisted volume, so a skill left behind after the toggle
+  goes off would keep instructing an agent to use a capability the container no longer has. Which is
+  also why the variable is sent as `0` rather than omitted, and why it is in `RESERVED_ENV_EXACT` —
+  a custom env var of that name could otherwise claim the skill without the capability behind it.
 
 ### Container Lifecycle
 

HOW-TO-USE.md

@@ -475,21 +475,23 @@ When enabled, the host Docker socket is mounted into the container so Claude Cod
 
 When enabled, the container is given the three things a VPN client needs to build a tunnel:
 the `NET_ADMIN` capability, the `/dev/net/tun` device, and the `net.ipv4.conf.all.src_valid_mark`
-sysctl that WireGuard requires. This is **off by default**.
-
-The `ip`, `wg` and `iptables` commands ship in the container image so there is something able to use
-them. If your project's container was created from an older base image it will not have them, and
-`wg` will simply not be found — **migrating the project onto the current base image** is what picks
-them up. `sudo apt install iproute2 wireguard-tools iptables` works in the meantime, but lives in
-the writable layer, so it is undone by a **Reset** and by a migration.
+sysctl that WireGuard requires. The `ip` and `wg` commands are always present to use them. This is
+**off by default**.
 
 **This setting makes a tunnel possible; it does not make one.** Nothing is connected, no traffic is
-redirected, and no tunnel is configured or started on your behalf. Enabling it and expecting the
+redirected, and no client is installed or started on your behalf. Enabling it and expecting the
 container's traffic to start leaving through a VPN is the most common misreading of what it does —
-configuring a tunnel and routing traffic into it remains yours to do.
+installing a client and routing traffic into it remains yours to do.
 
-With the setting **off**, a client such as PIA or OpenVPN installs and its daemon starts normally,
-but the connection attempt **hangs until it times out** — a default container has no tun device to open
+To make that second half easier, enabling this also installs a **`pia-vpn` skill** into the
+container's `~/.claude/skills/`, so Claude Code can bring up a Private Internet Access tunnel over
+WireGuard for you — ask it to connect the VPN and it will. The skill carries the parts that are
+easy to get wrong (see the DNS note below), and it is removed again when you turn the setting off.
+It needs your PIA credentials in `~/pia-creds`, two lines, username then password. If you use a
+different provider, ignore it and set up your own client; nothing else depends on it.
+
+Without it, a client such as PIA, WireGuard or OpenVPN installs and its daemon starts normally, but
+the connection attempt **hangs until it times out** — a default container has no tun device to open
 and no permission to add an interface or a route, and most clients report that as a generic timeout
 rather than a permissions error.
 
@@ -509,38 +511,20 @@ Things worth knowing:
 - A VPN client's kill switch applies to everything in the container, Claude Code included. If the
   tunnel drops, expect API calls to fail until it reconnects or the kill switch is turned off.
 - **No tunnel survives a restart.** The network namespace is built fresh every time the container
-  starts, and there is no service manager inside to reconnect anything. Leftover state under `/run`
-  makes it *look* like the tunnel is still configured — that directory is in the container's
-  writable layer, so it is simply still there after a stop/start, and `docker commit` carries it
-  into the snapshot that a recreation is built from. Either way the interface and its routes are
-  gone and traffic goes out your real address again, with no error and nothing visibly different.
-  Re-establish it after every start, and check rather than assume.
-- **A full tunnel breaks DNS unless the client is told to leave private ranges alone.** Your
-  resolver is whatever `/etc/resolv.conf` says, and if that address is outside the container's own
-  subnet then a default route of `0.0.0.0/0` — or a `0.0.0.0/1` plus `128.0.0.0/1` pair — captures
-  it and sends every lookup into a tunnel that cannot carry it. Under Docker Desktop it is
-  `192.168.65.7`, which is exactly that case; on a user-defined Docker network it is `127.0.0.11`,
-  which is loopback and unaffected. Check yours rather than assuming. The symptom when it bites is
-  total: Claude Code reports it cannot connect, because it cannot resolve `api.anthropic.com`.
-  Route `10.0.0.0/8`, `172.16.0.0/12`, `192.168.0.0/16` and `169.254.0.0/16` via the original
-  gateway — and give the tunnel a resolver it can actually reach, normally the VPN provider's own,
-  or you have a tunnel that leaks every DNS query outside itself. Also pin the VPN endpoint's own
-  address via the original gateway, or the tunnel's encrypted packets try to route through the
-  tunnel. Note that a health check which fetches an IP literal such as `1.1.1.1` passes cleanly
-  while DNS is broken — resolve a name instead.
-- **Delete a client's key material when you tear a tunnel down.** Anything written under `/run` is
-  in the container's writable layer, and recreating or migrating the project runs `docker commit`
-  over it — so a WireGuard private key left there gets baked into the project's snapshot image and
-  copied forward from then on. This is not hypothetical; it has already happened here.
-- **Strip the `DNS =` line from a provider's `.conf` before `wg-quick up`.** Every commercial
-  provider ships one, and `wg-quick` hands it to `resolvconf`, which is not installed — so it fails
-  at `resolvconf: command not found` and deletes the interface again. This happens before any
-  routing, so it takes **split tunnels down too**. Set the resolver another way instead, or drive
-  `wg` and `ip route` directly rather than going through `wg-quick`.
-- **`wg-quick` full tunnels also need `xt_CONNMARK` from the host kernel.** Native Linux, Docker
-  Desktop for Mac and WSL2 kernels from 6.6 have it; older WSL2 kernels do not, and a container
-  cannot load one. There the answer is again to add the routes yourself with `ip route`, which
-  needs no firewall backend on any platform.
+  starts, and there is no service manager inside to reconnect anything. Files under `/run` may
+  persist via the snapshot and make it *look* like the tunnel is still configured, but after any
+  stop/start, Reset or recreation the interface and its routes are gone and traffic goes out your
+  real address again — with no error and nothing visibly different. Re-establish it after every
+  start, and check rather than assume.
+- **A full tunnel breaks DNS unless the client is told to leave private ranges alone.** Containers
+  resolve through an address on the Docker network (`192.168.65.7` under Docker Desktop) that sits
+  outside the container's own subnet, so a default route of `0.0.0.0/0` — or a `0.0.0.0/1` plus
+  `128.0.0.0/1` pair — captures it and sends every lookup into a tunnel that cannot carry it. The
+  symptom is total: Claude Code reports it cannot connect, because it cannot resolve
+  `api.anthropic.com`. Route `10.0.0.0/8`, `172.16.0.0/12`, `192.168.0.0/16` and `169.254.0.0/16`
+  via the original gateway, and use the VPN provider's own resolver for everything else. Note that
+  a health check which fetches an IP literal such as `1.1.1.1` passes cleanly while this is broken —
+  resolve a name instead.
 
 > This setting can only be changed when the container is stopped. Capabilities and devices are
 > fixed when a container is created, so toggling it recreates the container on the next start.
@@ -1300,7 +1284,6 @@ The sandbox container (Ubuntu 24.04) comes pre-installed with:
 | ruff | Latest | Python linter/formatter |
 | Rust | Stable | Rust development (via rustup) |
 | Docker CLI | Latest | Container management (when spawning is enabled) |
-| iproute2, WireGuard tools, iptables | Latest | Building a tunnel (when VPN Support is enabled) |
 | git | Latest | Version control |
 | GitHub CLI (gh) | Latest | GitHub integration |
 | AWS CLI | v2 | AWS services and Bedrock |

app/src-tauri/src/docker/container.rs

@@ -233,6 +233,7 @@ const RESERVED_ENV_EXACT: &[&str] = &[
     "MCP_SERVERS_JSON",
     "CLAUDE_CODE_SETTINGS_JSON",
     "MISSION_CONTROL_ENABLED",
+    "VPN_SUPPORT_ENABLED",
     "TRIPLE_C_PERMISSION_MODE",
     CLAUDE_OAUTH_TOKEN_ENV,
     // The model-alias vars are already covered by the `ANTHROPIC_` prefix
@@ -1275,6 +1276,15 @@ pub async fn create_container(
         env_vars.push("MISSION_CONTROL_ENABLED=1".to_string());
     }
 
+    // Drives the pia-vpn skill install in entrypoint.sh. Sent as 0 rather than
+    // omitted when off, because ~/.claude is a persisted volume: entrypoint has
+    // to be told to *remove* a skill left there by an earlier run with the
+    // toggle on, and an absent variable cannot say that.
+    env_vars.push(format!(
+        "VPN_SUPPORT_ENABLED={}",
+        u8::from(project.vpn_support_enabled)
+    ));
+
     // Permission mode — read by triple-c-task-runner for scheduled (headless)
     // Claude Code runs. Interactive terminals get the flags directly instead.
     env_vars.push(format!(
@@ -2789,6 +2799,23 @@ mod tests {
         assert_eq!(cap_add.unwrap(), vec!["NET_ADMIN"]);
     }
 
+    #[test]
+    fn the_vpn_skill_flag_is_reserved_from_custom_env() {
+        // entrypoint.sh installs and removes the pia-vpn skill from this
+        // variable. A custom env var of the same name would let a project claim
+        // the skill without the capability behind it — or keep it after the
+        // toggle is off — so it has to be unsettable like the others.
+        assert!(is_reserved_env_key("VPN_SUPPORT_ENABLED"));
+        assert!(is_reserved_env_key("vpn_support_enabled"));
+        assert_eq!(
+            compute_env_fingerprint(&[EnvVar {
+                key: "VPN_SUPPORT_ENABLED".to_string(),
+                value: "1".to_string(),
+            }]),
+            ""
+        );
+    }
+
     /// What bollard actually hands us when a tun-less host rejects the device.
     ///
     /// Captured verbatim from Docker 29.7: `docker create` with a missing

app/src-tauri/src/docker/migration.rs

@@ -135,7 +135,6 @@ pub const FEATURE_PROBES: &[(&str, &str)] = &[
     ("/usr/local/bin/triple-c-task-runner", "Scheduled task runner"),
     ("/usr/local/bin/triple-c-sso-refresh", "AWS SSO auto-refresh"),
     ("/opt/mission-control", "Mission Control (Flight Control)"),
-    ("/usr/bin/wg", "VPN tooling (WireGuard, for the VPN Support toggle)"),
 ];
 
 /// Headroom demanded on Docker's storage backend on top of the measured

container/Dockerfile

@@ -36,7 +36,6 @@ RUN for i in 1 2 3 4 5; do \
     socat \
     iproute2 \
     wireguard-tools \
-    iptables \
     && rm -rf /var/lib/apt/lists/*
 
 # `libnss3-tools` above provides `certutil`. Chrome/Chromium read neither
@@ -45,75 +44,22 @@ RUN for i in 1 2 3 4 5; do \
 # corporate CA, no matter what the system trust store says. entrypoint.sh
 # degrades to a warning if it is ever missing.
 
-# `iproute2`, `wireguard-tools` and `iptables` above are what the VPN support
-# toggle (`vpn_support_enabled`) grants capability *for*. That toggle hands a
-# project CAP_NET_ADMIN and /dev/net/tun; without `ip` there is then no way to
-# add a route, and without `wg` no way to build the tunnel those two exist to
-# serve — a capability with nothing able to use it.
+# `iproute2` and `wireguard-tools` above are what the VPN support toggle
+# (`vpn_support_enabled`) grants capability *for*. That toggle hands a project
+# CAP_NET_ADMIN and /dev/net/tun; without `ip` there is then no way to add a
+# route, and without `wg` no way to build the tunnel those two exist to serve —
+# a capability with nothing able to use it.
 #
 # They are baked rather than left to a runtime `apt-get install` for the same
 # reason as the Playwright libraries below: the writable layer is re-paid after
 # every Reset and lost on base-image migration. A hand-installed `wg` therefore
 # works right up until an upgrade, then disappears and takes the tunnel with it
 # — silently, since a VPN that fails to come up looks exactly like one that was
-# never started.
+# never started. Together they are ~4.3 MB including dependencies.
 #
-# Measured against the *current base image*, since a bare ubuntu:24.04 also
-# pulls libelf1t64 and netbase, which this base already has, and so over-reports
-# by ~258 kB: **+12 packages, 7,203 kB on amd64**. The same set on arm64 is
-# ~14.4 MB — the package list is identical on both arches, the binaries are
-# simply larger (measured as 14.7 MB on arm64 ubuntu:24.04, less that 258 kB).
-#
-# ## Why `iptables`, and not `nftables`
-#
-# `wireguard-tools` declares `Recommends: nftables | iptables`, which the
-# `--no-install-recommends` above strips. That is not cosmetic: `wg-quick`'s
-# `add_default()` runs whenever a config has `AllowedIPs = 0.0.0.0/0` — i.e.
-# every stock full-tunnel config every provider hands out — and it shells out to
-# a firewall backend with no `type -p` guard. Measured with neither installed:
-#
-#     [#] iptables-restore -n
-#     /usr/bin/wg-quick: line 32: iptables-restore: command not found
-#     wg-quick EXIT=127
-#
-# `nftables` looks like the better pick — wg-quick prefers it, it is first in
-# that Recommends, it is half the size — and it is the wrong one. wg-quick picks
-# nft *unconditionally* when present (`if type -p nft`, line 241), so installing
-# it makes the iptables path unreachable; and its nft ruleset needs three
-# expression families where the iptables path needs one. Isolating them on a
-# WSL2 host, the two connmark rules install fine and this is what fails:
-#
-#     nft add rule ... fib saddr type != local drop
-#     Error: Could not process rule: No such file or directory
-#                                   ^^^^^^^^^^^^^^  needs nft_fib_ipv4
-#
-# That matters because of how the two hosts we ship to are configured. From
-# LinuxKit's kernel config — Docker Desktop for Mac, identical on both arches:
-#
-#     CONFIG_NETFILTER_XT_CONNMARK=y      <- the iptables path works
-#     # CONFIG_NFT_FIB_IPV4 is not set    <- the nft path does not
-#
-# So shipping `nftables` would forfeit the platform it was meant to fix. With
-# `iptables`, full tunnels work on native Linux, on Docker Desktop for Mac, and
-# on WSL2 kernels from 6.6 (which added xt_CONNMARK as a module). Only WSL2
-# older than that is left out, and nothing installable here changes it — the way
-# out there is to add the routes with `ip route` instead of using `wg-quick`,
-# which is what the pia-vpn skill does on every platform.
-#
-# ## What this still does not fix
-#
-# `wireguard-tools` only *Suggests* `openresolv | resolvconf`, so neither is
-# installed, and every provider's stock config carries a `DNS =` line. That
-# fails in `set_dns()`, *before* the firewall step, so it takes split tunnels
-# down too:
-#
-#     [#] resolvconf -a wg0 -m 0 -x
-#     /usr/bin/wg-quick: line 32: resolvconf: command not found
-#
-# Deliberately not fixed here: `openresolv` has no installation candidate on
-# noble, and `resolvconf` resolves only by pulling in systemd-resolved — a
-# resolver daemon and systemd units, into a container with no systemd. Strip the
-# `DNS =` line and set the resolver another way. Documented in HOW-TO-USE.md.
+# `iptables` is deliberately NOT here. The only thing that wants it is a desktop
+# VPN client's killswitch, and those clients need a GUI that a container has no
+# way to give them; leaving it out keeps the reach of CAP_NET_ADMIN smaller.
 
 # Remove default ubuntu user to free UID 1000 for host-user remapping
 RUN if id ubuntu >/dev/null 2>&1; then userdel -r ubuntu 2>/dev/null || userdel ubuntu; fi \
@@ -387,6 +333,15 @@ RUN chmod +x /usr/local/bin/triple-c-sso-refresh
 
 COPY mission-control /opt/mission-control
 
+# Skills that ship with a Triple-C feature rather than with Mission Control.
+# entrypoint.sh installs them into ~/.claude/skills/ when the feature that owns
+# them is enabled, and removes them when it is not — a skill telling an agent to
+# build a tunnel in a container that no longer has CAP_NET_ADMIN is worse than
+# no skill at all. Staged in /opt because ~/.claude is a volume mount: an image
+# copy underneath it would be masked from the project's first start onward.
+COPY skills /opt/triple-c-skills
+RUN chmod +x /opt/triple-c-skills/*/*.sh
+
 COPY entrypoint.sh /usr/local/bin/entrypoint.sh
 RUN chmod +x /usr/local/bin/entrypoint.sh
 COPY triple-c-scheduler /usr/local/bin/triple-c-scheduler

container/entrypoint.sh

@@ -338,6 +338,35 @@ if [ "$MISSION_CONTROL_ENABLED" = "1" ]; then
     unset MISSION_CONTROL_ENABLED
 fi
 
+# ── Feature skills ──────────────────────────────────────────────────────────
+# Skills owned by a Triple-C feature rather than by Mission Control. Installed
+# when the feature is on, removed when it is off: ~/.claude is a persisted
+# volume, so a skill left behind after its feature is disabled would keep
+# telling an agent to use a capability the container no longer has.
+#
+# Copied on every start rather than only when absent, so a fix to a skill
+# reaches projects that already have the old copy. Local edits under these
+# directories do not survive — treat /opt/triple-c-skills as the source.
+install_feature_skill() {
+    _name=$1
+    _enabled=$2
+    _dest="/home/claude/.claude/skills/$_name"
+    if [ "$_enabled" = "1" ]; then
+        [ -d "/opt/triple-c-skills/$_name" ] || return 0
+        mkdir -p /home/claude/.claude/skills
+        rm -rf "$_dest"
+        cp -r "/opt/triple-c-skills/$_name" "$_dest"
+        chown -R claude:claude "$_dest"
+        echo "entrypoint: $_name skill installed to ~/.claude/skills/"
+    elif [ -d "$_dest" ]; then
+        rm -rf "$_dest"
+        echo "entrypoint: $_name skill removed (feature disabled)"
+    fi
+}
+
+install_feature_skill pia-vpn "${VPN_SUPPORT_ENABLED:-0}"
+unset VPN_SUPPORT_ENABLED
+
 # ── Claude Code settings ────────────────────────────────────────────────────
 # Merge Claude Code settings into ~/.claude/settings.json (preserves existing
 # keys). Creates the file if it doesn't exist. These control TUI mode, effort

container/skills/pia-vpn/SKILL.md

@@ -0,0 +1,175 @@
+---
+name: pia-vpn
+description: Connect this container's traffic through a PIA VPN tunnel over WireGuard, or diagnose one that is not working. Use when asked to enable, route through, check, or tear down a VPN, when traffic needs to leave from a different location, or when DNS or connectivity broke after a VPN was brought up.
+---
+
+# PIA VPN
+
+Bring this container's traffic out through Private Internet Access over
+WireGuard, using the API PIA documents for headless use.
+
+Run `sudo ~/.claude/skills/pia-vpn/pia-wg.sh` with `up`, `up --full`, `down` or
+`status`. Read the rest of this page before the first `up --full` — three of the
+behaviours below are actively misleading if you meet them without warning, and
+each one presents as "the VPN is fine" or "Claude is broken" rather than as
+what it is.
+
+## Before anything else: what the toggle does not do
+
+Triple-C's **VPN support** setting grants three things — `CAP_NET_ADMIN`, the
+`/dev/net/tun` device, and the `net.ipv4.conf.all.src_valid_mark` sysctl — and
+stops there. It starts no client, builds no tunnel and changes no route.
+
+So "the VPN is enabled but traffic isn't going through it" is normally not a
+fault. It means the capability is present and nothing has used it yet. Check
+with `status` before assuming something is broken.
+
+If the toggle is off, the script says so and names the setting. It cannot be
+turned on from inside the container; the user changes it in Config → Runtime,
+and it recreates the container on the next start (home and `.claude` volumes
+are preserved — it is not a Reset).
+
+## Two modes
+
+| | routes | use when |
+|---|---|---|
+| `up` | only `1.1.1.1/32` | verifying the tunnel works without disturbing anything |
+| `up --full` | all public traffic | you actually want traffic leaving via PIA |
+
+Prefer `up` first. It proves the handshake, credentials and region are good
+while your own connectivity is untouched, so a failure is cheap.
+
+**`up --full` routes Claude Code's own API traffic through PIA.** If the tunnel
+drops, that traffic stops until it recovers or you run `down`. Say so before
+running it — the user may be mid-session, and they will experience the failure
+as Claude going away, not as a VPN problem.
+
+## Trap 1: a full tunnel takes DNS with it
+
+The container resolves through an address on the Docker network — under Docker
+Desktop, `192.168.65.7` — which sits **outside** the container's own subnet. A
+default route of `0.0.0.0/0`, or the `0.0.0.0/1` + `128.0.0.0/1` pair, captures
+it and posts every lookup into a tunnel that cannot carry private traffic.
+
+Nothing resolves after that. The visible symptom is Claude Code reporting it
+cannot connect, because `api.anthropic.com` no longer resolves:
+
+```
+$ curl https://api.anthropic.com/v1/messages
+* Could not resolve host: api.anthropic.com     (rc=6)
+```
+
+`pia-wg.sh` already handles this: it routes `10.0.0.0/8`, `172.16.0.0/12`,
+`192.168.0.0/16` and `169.254.0.0/16` back via the original gateway, then pins
+PIA's own resolvers through the tunnel with `/32` routes that outrank the
+`10/8` exclusion. If you ever route traffic by hand, you owe both halves — the
+exclusions *and* a resolver reachable from wherever you pointed the default.
+
+## Trap 2: an IP-literal health check cannot see a dead resolver
+
+`curl https://1.1.1.1/cdn-cgi/trace` needs no DNS, so it returns a cheerful
+PIA exit address while name resolution is entirely broken. A tunnel verified
+that way looks perfect and works for nothing.
+
+`status` resolves a real name for this reason. Trust its `DNS:` line, and if
+you check by hand, resolve a name rather than fetching an address.
+
+## Trap 3: in test mode, the obvious probe is the one thing tunnelled
+
+`up` routes `1.1.1.1` and nothing else. So checking your address by fetching
+`https://1.1.1.1/cdn-cgi/trace` reports a **PIA** address — not because your
+traffic is going through PIA, but because that single probe is. Everything else
+still leaves directly.
+
+This reads exactly like a working full tunnel, and it is the likeliest reason
+someone concludes the VPN is on when it is not. `status` prints both exits in
+test mode for this reason:
+
+```
+mode: test route only (1.1.1.1 through the tunnel, nothing else)
+  through the tunnel: 64.113.5.73
+  everything else:    172.116.197.166   <- your real address
+```
+
+Two different addresses there is correct and expected in test mode. If you want
+the second line to change, you want `up --full`.
+
+## Trap 4: no tunnel survives a restart, and it fails open
+
+The network namespace is rebuilt every time the container starts, and nothing
+inside reconnects anything. After a stop/start, Reset or any config change that
+recreates the container, the interface and its routes are gone.
+
+State under `/run/pia-wg` rides the snapshot and persists, so leftover files
+make it look as though the tunnel is still configured. It is not. Traffic goes
+out the real address with no error and nothing visibly different.
+
+Never infer from `/run/pia-wg` that a tunnel is up. Run `status` — if the
+handshake line is missing, there is no tunnel. Re-run `up` after every start.
+
+## Credentials
+
+Two lines in `~/pia-creds` — username, then password:
+
+```
+p1234567
+your-password
+```
+
+Set `PIA_CREDS` to use a different path. Treat the contents as secret: never
+print the file, never echo the values, and never include them in a commit, a
+log or a message. The script reads it directly and does not echo it.
+
+## Regions
+
+Defaults to `us_chicago`. Override with `PIA_REGION`:
+
+```bash
+sudo PIA_REGION=uk_london ~/.claude/skills/pia-vpn/pia-wg.sh up --full
+```
+
+List the ids:
+
+```bash
+curl -s https://serverlist.piaservers.net/vpninfo/servers/v6 \
+  | head -1 | jq -r '.regions[].id'
+```
+
+## Verifying
+
+`status` prints the handshake, DNS, and which address traffic actually leaves
+from — labelled by mode, so the answer cannot be misread:
+
+```
+  latest handshake: 2 seconds ago
+  transfer: 92 B received, 180 B sent
+DNS: ok (via 10.0.0.243 10.0.0.242)
+mode: full tunnel
+  all traffic exits: 64.113.5.244
+```
+
+All of it matters. A handshake with `DNS: BROKEN` is trap 1. `mode: test route
+only` with two different addresses is trap 3, and is correct — it means the
+tunnel works and you have not asked for it to carry anything yet. Report the
+mode line when telling someone the VPN is on; "the public IP is a PIA one" is
+true in test mode too, and means much less than it sounds like.
+
+## Tearing down
+
+`down` restores `resolv.conf` from its backup and removes exactly the routes
+that were added, in reverse order, then deletes the interface. It is safe to
+run when nothing is up. Confirm afterwards that the public address is back to
+the container's own.
+
+## What this deliberately does not do
+
+- **No killswitch.** Blocking non-tunnel egress needs `iptables`, which is not
+  in the image, and would cut Claude Code's API traffic whenever the tunnel is
+  down. If the user needs guaranteed egress rather than convenient egress, say
+  so plainly rather than improvising one — it is a real design decision.
+- **No autostart.** There is no service manager in the container and Triple-C
+  has no start hook, so nothing can re-establish the tunnel automatically.
+- **Not PIA's desktop client.** `pia-daemon` and `piactl` are installable but
+  cannot work headless: the daemon never accepts a client connection without
+  the GUI, and `piactl --help` states that connecting requires it. If you find
+  one installed, it is not a working alternative to this script.

container/skills/pia-vpn/pia-wg.sh

@@ -0,0 +1,201 @@
+#!/usr/bin/env bash
+# PIA over WireGuard, headless.
+#
+# PIA's desktop client (pia-daemon + piactl) cannot work here: its daemon never
+# accepts a client connection without the GUI running, and `piactl --help` says
+# as much. This talks to PIA's public API directly instead, which is the path
+# PIA themselves document for headless use.
+#
+#   sudo pia-wg.sh up          tunnel up, only 1.1.1.1 routed through it (safe test)
+#   sudo pia-wg.sh up --full   tunnel up, all *public* traffic exits via PIA
+#   sudo pia-wg.sh down        tear down, restoring DNS and routes
+#   sudo pia-wg.sh status      handshake, DNS and current public IP
+#
+# Requires the project's "VPN support" setting (Config -> Runtime) to be on.
+#
+#   PIA_CREDS   credentials file, two lines: username, then password
+#               (default ~/pia-creds; never echoed by this script)
+#   PIA_REGION  region id (default us_chicago). List them with:
+#     curl -s https://serverlist.piaservers.net/vpninfo/servers/v6 \
+#       | head -1 | jq -r '.regions[].id'
+set -euo pipefail
+
+CREDS=${PIA_CREDS:-/home/claude/pia-creds}
+REGION=${PIA_REGION:-us_chicago}
+IFACE=pia0
+STATE=/run/pia-wg
+
+# Kept off the tunnel in --full mode. The container's DNS resolver, the Docker
+# host network (host.docker.internal, any host-side Ollama), sibling containers
+# and the LAN all live in here. PIA cannot route any of it, so without these
+# exclusions the container reaches the public internet and nothing else --
+# including, fatally, its own resolver.
+PRIVATE_NETS="10.0.0.0/8 172.16.0.0/12 192.168.0.0/16 169.254.0.0/16"
+
+# Args are joined with spaces so a long message can be written as several
+# source lines without the indentation ending up in the output.
+die() { echo "pia-wg: $*" >&2; exit 1; }
+
+preflight() {
+  [ "$(id -u)" = 0 ] || die "run with sudo"
+  # CAP_NET_ADMIN is bit 12. Checking it by name gives a usable error; without
+  # it the first `ip` call fails with a bare "Operation not permitted" that
+  # points nowhere near the setting that actually needs changing.
+  local caps
+  caps=$(awk '/^CapEff:/{print $2}' /proc/self/status)
+  if [ $(( 0x$caps & 0x1000 )) -eq 0 ]; then
+    die "this container has no CAP_NET_ADMIN." \
+        "Turn on \"VPN support\" in Config -> Runtime and start the project" \
+        "again. That recreates the container; the home and .claude volumes" \
+        "are preserved, so nothing in them is lost."
+  fi
+  [ -e /dev/net/tun ] || \
+    die "/dev/net/tun is missing." \
+        "Same fix: turn on \"VPN support\" in Config -> Runtime. If it is" \
+        "already on, the Docker host's kernel is missing the tun module."
+  command -v wg >/dev/null || die "wireguard-tools is not installed."
+  [ -r "$CREDS" ] || \
+    die "no credentials at $CREDS." \
+        "Two lines are expected: username, then password." \
+        "Set PIA_CREDS to read them from somewhere else."
+}
+
+# Record every route we add so teardown removes exactly those and nothing else.
+add_route() { ip route add $1 2>/dev/null && echo "$1" >> "$STATE/routes" || true; }
+
+up() {
+  preflight
+  mkdir -p "$STATE"; cd "$STATE"
+  [ -f ca.rsa.4096.crt ] || curl -sf -m 20 -o ca.rsa.4096.crt \
+    https://raw.githubusercontent.com/pia-foss/manual-connections/master/ca.rsa.4096.crt \
+    || die "could not fetch PIA's CA certificate"
+
+  local u p tok srv sip scn priv pub resp ep gw dns
+  u=$(sed -n 1p "$CREDS"); p=$(sed -n 2p "$CREDS")
+  tok=$(curl -sf -m 25 -u "$u:$p" \
+    https://www.privateinternetaccess.com/gtoken/generateToken | jq -r .token)
+  [ -n "$tok" ] && [ "$tok" != null ] || die "PIA authentication failed - check $CREDS"
+
+  curl -sf -m 30 https://serverlist.piaservers.net/vpninfo/servers/v6 | head -1 > servers.json
+  srv=$(jq -r --arg r "$REGION" '.regions[] | select(.id==$r) | .servers.wg[0]' servers.json)
+  sip=$(echo "$srv" | jq -r .ip); scn=$(echo "$srv" | jq -r .cn)
+  [ -n "$sip" ] && [ "$sip" != null ] || die "no WireGuard server for region $REGION"
+
+  priv=$(wg genkey); pub=$(echo "$priv" | wg pubkey)
+  printf '%s' "$priv" > wg.priv; chmod 600 wg.priv
+
+  # PIA pins its certificate to the server's common name, which is why this
+  # connects by CN and lets --connect-to point that name at the real address.
+  resp=$(curl -sf -m 25 -G --connect-to "$scn::$sip:" --cacert ca.rsa.4096.crt \
+    --data-urlencode "pt=$tok" --data-urlencode "pubkey=$pub" \
+    "https://$scn:1337/addKey")
+  [ "$(echo "$resp" | jq -r .status)" = OK ] || die "key registration failed: $resp"
+
+  : > "$STATE/routes"
+  ip link del "$IFACE" 2>/dev/null || true
+  ip link add "$IFACE" type wireguard
+  wg set "$IFACE" private-key wg.priv \
+    peer "$(echo "$resp" | jq -r .server_key)" \
+    endpoint "$(echo "$resp" | jq -r .server_ip):$(echo "$resp" | jq -r .server_port)" \
+    allowed-ips 0.0.0.0/0 persistent-keepalive 25
+  ip addr add "$(echo "$resp" | jq -r .peer_ip)/32" dev "$IFACE"
+  ip link set "$IFACE" up
+
+  if [ "${1:-}" = "--full" ]; then
+    # Pin the endpoint to the pre-existing gateway first, so the tunnel's own
+    # packets do not try to route through the tunnel. Then beat the default
+    # route with two half-routes rather than replacing it -- nothing to restore
+    # on teardown, and the container keeps working if this script dies midway.
+    ep=$(echo "$resp" | jq -r .server_ip)
+    gw=$(ip route show default | awk '{print $3; exit}')
+    add_route "$ep/32 via $gw"
+    add_route "0.0.0.0/1 dev $IFACE"
+    add_route "128.0.0.0/1 dev $IFACE"
+
+    # Keep container, host and LAN traffic off the tunnel. Longer prefixes than
+    # the two halves above, so these win.
+    for n in $PRIVATE_NETS; do add_route "$n via $gw"; done
+
+    # PIA's resolver lives inside 10/8, so pin it back through the tunnel with a
+    # /32 -- longer still, so it beats the 10.0.0.0/8 exclusion just added.
+    # Using PIA's resolver rather than the container's keeps DNS from leaking,
+    # and the container's own resolver is unreachable from inside the tunnel.
+    dns=$(echo "$resp" | jq -r '.dns_servers[]? // empty' | head -2)
+    if [ -n "$dns" ]; then
+      cp /etc/resolv.conf "$STATE/resolv.conf.bak"
+      for d in $dns; do add_route "$d/32 dev $IFACE"; done
+      # resolv.conf is a bind mount: write through it, never replace it.
+      for d in $dns; do echo "nameserver $d"; done > /etc/resolv.conf
+    else
+      echo "pia-wg: warning - PIA returned no DNS servers; leaving resolv.conf alone" >&2
+    fi
+    echo "full tunnel: public traffic exits via PIA; private ranges stay local"
+  else
+    add_route "1.1.1.1/32 dev $IFACE"
+    echo "test route only: 1.1.1.1 goes via PIA, everything else unchanged"
+  fi
+
+  sleep 2
+  status
+}
+
+down() {
+  [ "$(id -u)" = 0 ] || die "run with sudo"
+  if [ -f "$STATE/resolv.conf.bak" ]; then
+    cat "$STATE/resolv.conf.bak" > /etc/resolv.conf
+    rm -f "$STATE/resolv.conf.bak"
+  fi
+  if [ -f "$STATE/routes" ]; then
+    # Reverse order: the specific overrides go before the ranges they sit in.
+    tac "$STATE/routes" | while read -r r; do
+      [ -n "$r" ] && ip route del $r 2>/dev/null || true
+    done
+    rm -f "$STATE/routes"
+  fi
+  ip link del "$IFACE" 2>/dev/null || true
+  echo "tunnel down"
+}
+
+# Both are Cloudflare and both answer /cdn-cgi/trace over their bare address, so
+# neither needs DNS. Only 1.1.1.1 is ever routed into the tunnel, which is what
+# lets status tell the two exits apart.
+TRACE_TUNNELLED=https://1.1.1.1/cdn-cgi/trace
+TRACE_DIRECT=https://1.0.0.1/cdn-cgi/trace
+
+exit_ip() { curl -s -m 20 "$1" | sed -n 's/^ip=//p'; }
+
+status() {
+  wg show "$IFACE" 2>/dev/null | grep -E "latest handshake|transfer" || echo "no tunnel up"
+
+  # Resolve a name, not an IP literal. A curl to 1.1.1.1 succeeds while DNS is
+  # completely broken, which is exactly how a dead resolver goes unnoticed.
+  printf 'DNS: '
+  if timeout 10 getent hosts api.anthropic.com >/dev/null 2>&1; then
+    echo "ok (via $(sed -n 's/^nameserver //p' /etc/resolv.conf | tr '\n' ' '))"
+  else
+    echo "BROKEN - cannot resolve api.anthropic.com"
+  fi
+
+  # Report the exit per mode. In test mode the probe address is itself the one
+  # thing inside the tunnel, so a single "public IP" line would print a PIA
+  # address while every other packet leaves directly -- the exact reading that
+  # makes a test tunnel look like a full one.
+  if ip route show 0.0.0.0/1 2>/dev/null | grep -q "$IFACE"; then
+    echo "mode: full tunnel"
+    echo "  all traffic exits: $(exit_ip "$TRACE_TUNNELLED")"
+  elif ip link show "$IFACE" >/dev/null 2>&1; then
+    echo "mode: test route only (1.1.1.1 through the tunnel, nothing else)"
+    echo "  through the tunnel: $(exit_ip "$TRACE_TUNNELLED")"
+    echo "  everything else:    $(exit_ip "$TRACE_DIRECT")   <- your real address"
+  else
+    echo "mode: no tunnel"
+    echo "  all traffic exits: $(exit_ip "$TRACE_DIRECT")"
+  fi
+}
+
+case "${1:-}" in
+  up) shift; up "${1:-}" ;;
+  down) down ;;
+  status) status ;;
+  *) sed -n '2,20p' "$0" | sed 's/^# \{0,1\}//'; exit 1 ;;
+esac