Link the agent half of user/ on the Mac mini

Manifest lines can now name an OS. The SSH config, pwswitch and espanso are
Linux only, so link-user on the Mac links CLAUDE.md, rules, skills and the
opencode commands and nothing else. link-mcp no longer aborts under the Mac's
bash 3.2 when a server has no token.

setup/scripts/link-mcp

@@ -157,14 +157,17 @@ while read -r name transport target token_var _rest; do
         continue
     fi
 
+    # ${args[@]+...} rather than "${args[@]}": the Mac's bash 3.2 treats an
+    # empty array as unset under set -u and aborts the whole stage.
+    #
     # Re-registering is how a new server or a rotated token reaches the
     # runtime. Removing first avoids the CLI refusing a name it already knows.
     # Neither call may print the token, so both are quiet unless they fail.
     claude mcp remove "$name" -s user >/dev/null 2>&1 || true
     if [[ "$transport" == stdio ]]; then
-        add=(claude mcp add "$name" -s user "${args[@]}" -- "$launcher")
+        add=(claude mcp add "$name" -s user ${args[@]+"${args[@]}"} -- "$launcher")
     else
-        add=(claude mcp add --transport "$transport" "$name" "$url" "${args[@]}" -s user)
+        add=(claude mcp add --transport "$transport" "$name" "$url" ${args[@]+"${args[@]}"} -s user)
     fi
     if "${add[@]}" >/dev/null 2>&1; then
         log "Registered $name."

setup/scripts/link-user

@@ -69,10 +69,12 @@ displace() {
 
 linked=0
 copied=0
+os="$(uname -s | tr '[:upper:]' '[:lower:]')"
 
-while read -r kind source destination; do
+while read -r kind source destination only_on _rest; do
     [[ -n "${kind:-}" ]] || continue
     [[ "$kind" == \#* ]] && continue
+    [[ -z "${only_on:-}" || "$only_on" == "$os" ]] || continue
 
     src="$USER_DIR/$source"
     dst="${destination/#\~/$HOME}"

tests/setup/user-content-contract

@@ -46,13 +46,15 @@ done < <(find "$repo_dir/user" -type f \( -name 'id_*' -o -name '*.pem' -o -name
 
 # ── Every manifest line is usable ───────────────────────────────────────────
 
-while read -r kind source destination; do
+while read -r kind source destination only_on; do
     [[ -e "$repo_dir/user/$source" ]] \
         || note "the manifest points at $source, which is not in user/"
     [[ "$kind" == link || "$kind" == linkdir || "$kind" == copy ]] \
         || note "the manifest uses an unknown kind: $kind"
     [[ "$destination" == '~/'* ]] \
         || note "the manifest destination $destination is not under the home directory"
+    [[ -z "$only_on" || "$only_on" == linux || "$only_on" == darwin ]] \
+        || note "the manifest names an unknown os: $only_on"
 done < <(grep -vE '^\s*(#|$)' "$manifest")
 
 # ── The behaviour, against a fake home ──────────────────────────────────────
@@ -77,6 +79,7 @@ linkdir  agents/skills     ~/.agents/skills
 linkdir  agents/skills     ~/.claude/skills
 copy     plain.txt         ~/.config/plain.txt
 link     missing.txt       ~/.config/missing.txt
+copy     plain.txt         ~/.config/elsewhere.txt  nosuchos
 FIXTURE
 
 home="$work/home"
@@ -141,6 +144,11 @@ fi
 grep -q 'missing.txt' "$work/log" \
     || note 'a skipped manifest entry was not reported'
 
+# A line naming another OS is for another machine. The Mac takes the agent half
+# of user/ and none of the Linux desktop half.
+[[ -e "$home/.config/elsewhere.txt" ]] \
+    && note 'a manifest entry for another OS was applied here'
+
 # ── The answer sticks ───────────────────────────────────────────────────────
 #
 # So that `panama upgrade` on a configured machine relinks without an interview,

user/README.md

@@ -86,6 +86,12 @@ Put the file under `user/`, add a line to `manifest`, run:
 Anything already at the destination is moved to `config/old/` rather than
 deleted, under a name that says where it came from.
 
+A line can end with `linux` or `darwin` to apply only on that OS. The Mac mini
+is not a Panama desktop, but it runs agents, so it takes the agent half of this
+directory and skips the SSH config, `pwswitch` and espanso. Panama's shipped
+skills describe the Linux desktop, so the Mac runs `link-user` and `link-mcp`
+only, never `link-skills`.
+
 ## What does not go in here
 
 Anything secret. This repository is readable by anyone who finds it, and the

user/manifest

@@ -1,6 +1,6 @@
 # What in user/ goes where, and in what form.
 #
-#   <kind>  <source under user/>  <destination>
+#   <kind>  <source under user/>  <destination>  [os]
 #
 # kind is one of:
 #   link   symlink the destination at the source, so editing either edits the
@@ -14,6 +14,10 @@
 #   copy   copy once, and never touch it again if the destination exists. Use
 #          this for files a machine legitimately diverges on.
 #
+# os is optional: linux or darwin, matched against `uname -s`. A line naming
+# one is skipped everywhere else. Leave it off for anything every machine
+# wants, which is most of this file; the Mac mini only takes the agent half.
+#
 # Lines beginning with # are comments and blank lines are ignored. ~ in a
 # destination is this user's home.
 #
@@ -43,21 +47,22 @@ link  agents/rules       ~/.claude/rules
 # ── SSH ──────────────────────────────────────────────────────────────────────
 # Host aliases only. Keys are per-machine and are never tracked; this is the
 # file that makes `ssh server` work the moment a machine is set up, and it is
-# what the SSH Hosts launcher command reads.
+# what the SSH Hosts launcher command reads. Linux only: it names id_ed25519
-link  ssh/config         ~/.ssh/config
+# and the desktop keyring's agent socket, and the Mac has neither.
+link  ssh/config         ~/.ssh/config  linux
 
 # ── Scripts ──────────────────────────────────────────────────────────────────
 # Personal commands wanted on every machine, desktop or server. ~/.local/bin is
 # on PATH in both shell configs. pwswitch toggles passwordless sudo through a
 # sudoers.d drop-in, so an agent can run sudo and the password comes back after.
-link  bin/pwswitch       ~/.local/bin/pwswitch
+link  bin/pwswitch       ~/.local/bin/pwswitch  linux
 
 # ── Espanso ──────────────────────────────────────────────────────────────────
 # The personal expansion triggers. Copied rather than linked, because this is a
 # file each machine may add its own triggers to. It lands before setup-identity
 # runs, and that stage only seeds a file that does not exist yet, so what is
 # tracked here wins over the name and email the interview would have written.
-copy  espanso/identity.yml  ~/.config/espanso/match/identity.yml
+copy  espanso/identity.yml  ~/.config/espanso/match/identity.yml  linux
 
 # ── OpenCode ─────────────────────────────────────────────────────────────────
 # Claude Code carries its commands and agents as plugins, which opencode cannot