fix(setup): install via the plugin marketplace flow, not a bare symlink

./setup symlinked the repo into ~/.claude/plugins/idstack. Current Claude
Code (2.1.x) does not discover plugins from bare symlinks — it requires a
marketplace registration — so `claude plugin list` showed nothing and
/idstack:<skill> never appeared in the slash-command picker.

Core fix:
- Add .claude-plugin/marketplace.json — the one-plugin marketplace manifest
  the install flow requires (source: "./", repo root).
- setup: Claude branch now runs `claude plugin marketplace add` +
  `claude plugin install --scope <user|project>` (both idempotent, so
  re-running setup is safe). --local maps to project scope. Detects when
  `claude` is missing on PATH and prints manual steps. Removes the now-
  vestigial bare symlink from prior installs (only ever a symlink, never a
  real dir). Codex branch unchanged.
- bin/idstack-doctor: rewritten to self-locate the repo and check the real
  signal — `claude plugin list` for idstack@idstack installed+enabled —
  plus the plugin + marketplace manifests. Keeps legacy-conflict detection;
  flags the vestigial symlink as an informational note.
- test/smoke-test.sh: $IDSTACK_DIR now self-locates the repo instead of
  assuming ~/.claude/plugins/idstack; legacy-conflict checks gate on "no $1
  override" instead of the old plugins-dir path. Adds marketplace.json
  assertions.
- templates/preamble.md: $_IDSTACK detection no longer falls back to the
  removed bare symlink; the last-ditch branch resolves the marketplace
  cache dir. Regenerated all 22 skill files (claude + codex).

Docs (README, docs/index.html, CONTRIBUTING, CLAUDE.md): install command
changes from `git clone … ~/.claude/plugins/idstack && …` to
`git clone … && cd idstack && ./setup`; update/troubleshooting text and
the doctor reference updated to match.

Verified: smoke-test 257/257, idstack-doctor OK, ./setup idempotent end
to end, gen-skills --dry-run clean.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: savvides

.claude-plugin/marketplace.json

@@ -0,0 +1,14 @@
+{
+  "name": "idstack",
+  "description": "Evidence-based instructional design pipeline — 11 skills backed by peer-reviewed research across 11 domains.",
+  "owner": {
+    "name": "Philippos Savvides",
+    "url": "https://github.com/savvides"
+  },
+  "plugins": [
+    {
+      "name": "idstack",
+      "source": "./"
+    }
+  ]
+}

CLAUDE.md

@@ -10,7 +10,7 @@ An open source set of skills for evidence-based instructional design. Runs in Cl
 
 ```bash
 ./setup              # Install idstack — auto-detects Claude Code and codex on PATH
-./setup --local      # Install to .claude/plugins/ in current project only
+./setup --local      # Install at project scope (./.claude/) instead of user scope
 ./setup --codex      # Force-install the Codex bundle even if codex isn't on PATH
 ./setup --no-codex   # Skip the Codex install
 ./test/smoke-test.sh # Verify installation, SKILL.md files, YAML frontmatter, migrations

CONTRIBUTING.md

@@ -40,7 +40,7 @@ allowed-tools:
 ---
 ```
 
-The bare `name` field becomes the slash-command suffix: `name: course-import` is invoked as `/idstack:course-import`. The plugin layout at `~/.claude/plugins/idstack/` handles the `idstack:` namespace; do not prefix the name yourself.
+The bare `name` field becomes the slash-command suffix: `name: course-import` is invoked as `/idstack:course-import`. The installed plugin handles the `idstack:` namespace; do not prefix the name yourself.
 
 **2. `{{PREAMBLE}}` placeholder** — this is replaced by `bin/idstack-gen-skills` with the shared preamble (update check, manifest check, context recovery).
 

README.md

@@ -101,12 +101,12 @@ You had a course in Canvas. Now you have an evidence-based audit with specific r
 Paste this into your terminal:
 
 ```bash
-git clone https://github.com/savvides/idstack.git ~/.claude/plugins/idstack
-cd ~/.claude/plugins/idstack
+git clone https://github.com/savvides/idstack.git
+cd idstack
 ./setup
 ```
 
-Restart Claude Code if it was already running — plugins load at session start. You should see `/idstack:<skill>` commands in the slash picker.
+`./setup` registers the repo as a Claude Code plugin marketplace and installs it. Restart Claude Code if it was already running — plugins load at session start. You should see `/idstack:<skill>` commands in the slash picker.
 
 ### Alternative install methods
 
@@ -115,7 +115,7 @@ Restart Claude Code if it was already running — plugins load at session start.
 
 If you'd rather not touch the terminal, paste this into Claude Code:
 
-> Install idstack: run `git clone https://github.com/savvides/idstack.git ~/.claude/plugins/idstack && cd ~/.claude/plugins/idstack && ./setup`, then tell me it's installed and show me the available skills.
+> Install idstack: run `git clone https://github.com/savvides/idstack.git && cd idstack && ./setup`, then tell me it's installed and show me the available skills.
 
 Claude clones the repo, runs setup, and confirms the skills are registered.
 </details>
@@ -275,7 +275,7 @@ Any skill works independently. Run `/idstack:pipeline` to chain them all, or inv
 +-------------------------------------------------------+
 ```
 
-Skills are plain Markdown files generated from templates. No build step for users, no dependencies. `./setup` registers the repo as a Claude Code plugin at `~/.claude/plugins/idstack`, which is what gives the namespaced `/idstack:<skill>` commands. Users invoke skills via `/idstack:<skill>`. Each skill reads the shared manifest and session history, runs its evidence-based workflow, writes back its section, and logs the session to the timeline. The pipeline adds context but every skill also works standalone.
+Skills are plain Markdown files generated from templates. No build step for users, no dependencies. `./setup` registers the repo as a Claude Code plugin marketplace and installs it, which is what gives the namespaced `/idstack:<skill>` commands. Users invoke skills via `/idstack:<skill>`. Each skill reads the shared manifest and session history, runs its evidence-based workflow, writes back its section, and logs the session to the timeline. The pipeline adds context but every skill also works standalone.
 
 ## How it works
 
@@ -366,7 +366,7 @@ idstack runs locally on your machine. Course data stays in your project folder (
 You can, but let the skills manage it. If you do edit it, keep the JSON valid.
 
 **How do I update idstack?**
-idstack checks for updates when you run any skill. If a newer version is available, you'll see a notification. Update manually: `cd ~/.claude/plugins/idstack && git pull && ./setup`
+idstack checks for updates when you run any skill. If a newer version is available, you'll see a notification. Update manually: `cd <your idstack clone> && git pull && ./setup`
 If you downloaded ZIP: download the latest version and run `./setup` again.
 
 **How do I request a feature or report a bug?**
@@ -379,18 +379,18 @@ idstack itself is just text files. But it runs inside Claude Code, which require
 
 **Skill not showing up?** Claude Code loads skills at session start. If you installed while Claude Code was running, restart it (close and reopen). If that doesn't help, run setup again:
 ```bash
-cd ~/.claude/plugins/idstack && ./setup
+cd <your idstack clone> && ./setup
 ```
 
 **Can't import a .imscc cartridge?** Make sure the file is a valid ZIP. Try re-exporting from your LMS with "Course" selected (not just content).
 
 **Canvas API says "token rejected"?** Generate a fresh token: Canvas -> Account -> Settings -> New Access Token. Tokens expire.
 
-**Claude says it can't find idstack skills?** Make sure you've run `./setup` after cloning. Setup registers the repo as a plugin at `~/.claude/plugins/idstack` so Claude Code discovers the namespaced `/idstack:<skill>` commands. Restart Claude Code after install — plugins load at session start.
+**Claude says it can't find idstack skills?** Make sure you've run `./setup` after cloning. Setup registers the repo as a plugin marketplace and installs it so Claude Code discovers the namespaced `/idstack:<skill>` commands. Restart Claude Code after install — plugins load at session start.
 
-**Upgrading from v2.0?** v2.0 installed under `~/.claude/skills/idstack`, which only exposed `/idstack` (the dispatcher) — never the 11 namespaced sub-skills. Re-clone to the new location: `git clone https://github.com/savvides/idstack.git ~/.claude/plugins/idstack && cd ~/.claude/plugins/idstack && ./setup`. Setup now detects and removes any pre-v2.0.1.0 install at `~/.claude/skills/idstack` (symlink *or* real directory). If you ran an older setup that only warned, run `./setup` once more — or remove it manually with `rm -rf ~/.claude/skills/idstack`.
+**Upgrading from v2.0?** v2.0 installed under `~/.claude/skills/idstack`, which only exposed `/idstack` (the dispatcher) — never the 11 namespaced sub-skills. Clone fresh and run setup: `git clone https://github.com/savvides/idstack.git && cd idstack && ./setup`. Setup now detects and removes any pre-v2.0.1.0 install at `~/.claude/skills/idstack` (symlink *or* real directory). If you ran an older setup that only warned, run `./setup` once more — or remove it manually with `rm -rf ~/.claude/skills/idstack`.
 
-**`/idstack:<skill>` won't autocomplete or returns "Unknown skill"?** Run `bin/idstack-doctor` from the plugin dir (`~/.claude/plugins/idstack`). It checks plugin presence, manifest version, all 11 SKILL.md files, and detects legacy-install conflicts — printing the exact remediation command for whatever it finds.
+**`/idstack:<skill>` won't autocomplete or returns "Unknown skill"?** Run `bin/idstack-doctor` from your idstack clone. It checks the plugin + marketplace manifests, the Claude Code install state, all 11 SKILL.md files, and detects legacy-install conflicts — printing the exact remediation command for whatever it finds.
 
 ## Contributing
 

bin/idstack-doctor

@@ -1,29 +1,30 @@
 #!/usr/bin/env bash
-# idstack install doctor — diagnose plugin / legacy-install conflicts.
+# idstack install doctor — diagnose plugin install + legacy conflicts.
 #
 # Answers: "is /idstack:<skill> going to work, and if not, exactly what
 # do I run?" without the user having to know about smoke-test.
 #
 # Usage:
-#   idstack-doctor               # check global install (~/.claude)
-#   idstack-doctor --local       # check local install (./.claude)
+#   idstack-doctor               # check user-scope install
+#   idstack-doctor --local       # also check project-scope legacy paths
 #
 # Exit code: 0 if all green, 1 if any problem is detected.
 
 set -u
 
+# This script lives at <repo>/bin/idstack-doctor — resolve the repo root from
+# its own location so the diagnosis works regardless of where the repo sits.
+IDSTACK_DIR="$(cd "$(dirname "$0")/.." && pwd -P)"
+
 SCOPE="global"
-CLAUDE_BASE="$HOME/.claude"
+LEGACY_BASE="$HOME/.claude"
 # Match --local in any position, not just $1. Robust if other flags get added.
 if [[ " ${*:-} " == *" --local "* ]]; then
   SCOPE="local"
-  CLAUDE_BASE="$(pwd)/.claude"
+  LEGACY_BASE="$(pwd)/.claude"
 fi
-
-PLUGINS_DIR="$CLAUDE_BASE/plugins"
-SKILLS_DIR="$CLAUDE_BASE/skills"
-PLUGIN_DIR="$PLUGINS_DIR/idstack"
-LEGACY_DIR="$SKILLS_DIR/idstack"
+LEGACY_SKILLS_DIR="$LEGACY_BASE/skills"
+LEGACY_DIR="$LEGACY_SKILLS_DIR/idstack"
 
 PROBLEMS=0
 note_problem() { PROBLEMS=$((PROBLEMS + 1)); }
@@ -33,67 +34,95 @@ assessment-design course-builder course-export accessibility-review red-team \
 pipeline learn"
 
 echo "idstack doctor ($SCOPE)"
-echo "  claude base: $CLAUDE_BASE"
+echo "  repo: $IDSTACK_DIR"
 echo ""
 
-# 1. Plugin presence
-echo "Plugin install:"
-if [ -e "$PLUGIN_DIR" ]; then
-  if [ -L "$PLUGIN_DIR" ]; then
-    target=$(readlink "$PLUGIN_DIR")
-    resolved=$(cd "$PLUGIN_DIR" 2>/dev/null && pwd -P || echo "BROKEN")
-    echo "  $PLUGIN_DIR -> $target"
-    if [ "$resolved" = "BROKEN" ]; then
-      echo "  PROBLEM: symlink target is missing or unreadable."
-      note_problem
-    fi
-  elif [ -d "$PLUGIN_DIR" ]; then
-    echo "  $PLUGIN_DIR (real directory)"
+# 1. Plugin + marketplace manifests in the repo
+echo "Plugin manifests:"
+plugin_manifest="$IDSTACK_DIR/.claude-plugin/plugin.json"
+market_manifest="$IDSTACK_DIR/.claude-plugin/marketplace.json"
+if [ -f "$plugin_manifest" ]; then
+  version=$(grep -o '"version": *"[^"]*"' "$plugin_manifest" | head -n1 | sed 's/.*"\([^"]*\)"$/\1/')
+  if [ -n "$version" ]; then
+    echo "  plugin.json present (version $version)"
   else
-    echo "  PROBLEM: $PLUGIN_DIR exists but is not a directory or symlink."
-    note_problem
-  fi
-  manifest="$PLUGIN_DIR/.claude-plugin/plugin.json"
-  if [ -f "$manifest" ]; then
-    version=$(grep -o '"version": *"[^"]*"' "$manifest" | head -n1 | sed 's/.*"\([^"]*\)"$/\1/')
-    if [ -n "$version" ]; then
-      echo "  manifest version: $version"
-    else
-      echo "  PROBLEM: could not parse version from $manifest"
-      note_problem
-    fi
-  else
-    echo "  PROBLEM: missing $manifest"
+    echo "  PROBLEM: could not parse version from $plugin_manifest"
     note_problem
   fi
 else
-  echo "  MISSING: $PLUGIN_DIR"
-  echo "  Run: ./setup   (from the idstack repo)"
+  echo "  PROBLEM: missing $plugin_manifest"
+  note_problem
+fi
+if [ -f "$market_manifest" ]; then
+  echo "  marketplace.json present"
+else
+  echo "  PROBLEM: missing $market_manifest"
+  echo "  Claude Code installs plugins through a marketplace manifest;"
+  echo "  without it, ./setup cannot register the plugin."
   note_problem
 fi
 echo ""
 
-# 2. Skill files reachable
+# 2. Skill files reachable in the repo
 echo "Skill files:"
 missing_skills=0
 for skill in $SKILLS; do
-  if [ ! -f "$PLUGIN_DIR/skills/$skill/SKILL.md" ]; then
+  if [ ! -f "$IDSTACK_DIR/skills/$skill/SKILL.md" ]; then
     echo "  MISSING: skills/$skill/SKILL.md"
     missing_skills=$((missing_skills + 1))
   fi
 done
 if [ "$missing_skills" = "0" ]; then
-  echo "  all 11 SKILL.md files reachable"
+  echo "  all 11 SKILL.md files present"
 else
-  echo "  PROBLEM: $missing_skills SKILL.md file(s) missing under the plugin"
+  echo "  PROBLEM: $missing_skills SKILL.md file(s) missing under skills/"
   note_problem
 fi
 echo ""
 
-# 3. Legacy install detection — the failure mode that surfaced as
-# "Unknown skill: idstack:course-import" / "Unknown skill: course-import".
+# 3. Claude Code install state — the marketplace flow records the plugin in
+# Claude Code's own registry; a bare symlink is not enough on current versions.
+echo "Claude Code install:"
+if command -v claude >/dev/null 2>&1; then
+  plugin_list=$(claude plugin list 2>/dev/null || true)
+  if echo "$plugin_list" | grep -q "idstack@idstack"; then
+    if echo "$plugin_list" | grep -A4 "idstack@idstack" | grep -qi "enabled"; then
+      echo "  idstack@idstack installed and enabled"
+    else
+      echo "  PROBLEM: idstack@idstack is installed but not enabled."
+      echo "  Fix: claude plugin enable idstack@idstack"
+      note_problem
+    fi
+  else
+    echo "  PROBLEM: idstack@idstack is not installed."
+    echo "  Fix: run ./setup from the repo, or manually:"
+    echo "    claude plugin marketplace add \"$IDSTACK_DIR\""
+    echo "    claude plugin install idstack@idstack"
+    note_problem
+  fi
+else
+  echo "  WARNING: 'claude' not found on PATH — cannot verify the install."
+  echo "           Install Claude Code, then run ./setup from the repo."
+fi
+echo ""
+
+# 4. Legacy / vestigial install conflicts.
 echo "Legacy install conflicts:"
 legacy_problem=0
+
+# Vestigial bare symlink from the pre-marketplace setup method. Harmless on
+# current Claude Code (ignored), but worth removing so it stops confusing
+# diagnostics. Informational, not counted as a problem.
+for plugins_base in "$HOME/.claude/plugins" "$(pwd)/.claude/plugins"; do
+  vestigial="$plugins_base/idstack"
+  if [ -L "$vestigial" ]; then
+    echo "  NOTE: vestigial symlink at $vestigial (pre-marketplace install method)."
+    echo "        Harmless — ./setup removes it. Or: rm \"$vestigial\""
+  fi
+done
+
+# Pre-v2.0.1.0 dispatcher install — the failure mode that surfaced as
+# "Unknown skill: idstack:course-import" / "Unknown skill: course-import".
 if [ -L "$LEGACY_DIR" ]; then
   target=$(readlink "$LEGACY_DIR")
   echo "  PROBLEM: legacy symlink at $LEGACY_DIR -> $target"
@@ -126,9 +155,9 @@ elif [ -d "$LEGACY_DIR" ]; then
     echo "           Not auto-removed. Inspect and remove manually if unwanted."
   fi
 fi
-# Pre-v2 individual skill symlinks pointing into idstack
+# Pre-v2 individual skill symlinks pointing into idstack.
 for skill in $SKILLS; do
-  link="$SKILLS_DIR/$skill"
+  link="$LEGACY_SKILLS_DIR/$skill"
   if [ -L "$link" ]; then
     t=$(readlink "$link" 2>/dev/null || true)
     if [[ "$t" == *"idstack"* ]]; then
@@ -145,7 +174,7 @@ else
 fi
 echo ""
 
-# 4. Final verdict
+# 5. Final verdict
 if [ "$PROBLEMS" = "0" ]; then
   echo "OK"
   exit 0

dist/codex/skills/idstack-accessibility-review/SKILL.md

@@ -47,14 +47,16 @@ if [ -n "${CLAUDE_PLUGIN_ROOT:-}" ]; then
   _IDSTACK="$CLAUDE_PLUGIN_ROOT"
 elif [ -n "${IDSTACK_HOME:-}" ]; then
   _IDSTACK="$IDSTACK_HOME"
-elif [ -d "$HOME/.claude/plugins/idstack" ]; then
-  _IDSTACK="$HOME/.claude/plugins/idstack"
 elif [ -d "$HOME/.agents/plugins/idstack" ]; then
   _IDSTACK="$HOME/.agents/plugins/idstack"
 elif [ -d "$HOME/.agents/skills/idstack" ]; then
   _IDSTACK="$HOME/.agents/skills/idstack"
 else
-  _IDSTACK="$HOME/.claude/plugins/idstack"
+  # Claude Code caches marketplace plugins under a versioned dir; take the
+  # highest version present. Empty if idstack was never installed this way —
+  # every "$_IDSTACK/bin/..." call below is guarded, so that degrades quietly.
+  _IDSTACK=$(ls -d "$HOME"/.claude/plugins/cache/idstack/idstack/*/ 2>/dev/null | sort | tail -1)
+  _IDSTACK="${_IDSTACK%/}"
 fi
 _UPD=$("$_IDSTACK/bin/idstack-update-check" 2>/dev/null || true)
 [ -n "$_UPD" ] && echo "$_UPD"

dist/codex/skills/idstack-assessment-design/SKILL.md

@@ -47,14 +47,16 @@ if [ -n "${CLAUDE_PLUGIN_ROOT:-}" ]; then
   _IDSTACK="$CLAUDE_PLUGIN_ROOT"
 elif [ -n "${IDSTACK_HOME:-}" ]; then
   _IDSTACK="$IDSTACK_HOME"
-elif [ -d "$HOME/.claude/plugins/idstack" ]; then
-  _IDSTACK="$HOME/.claude/plugins/idstack"
 elif [ -d "$HOME/.agents/plugins/idstack" ]; then
   _IDSTACK="$HOME/.agents/plugins/idstack"
 elif [ -d "$HOME/.agents/skills/idstack" ]; then
   _IDSTACK="$HOME/.agents/skills/idstack"
 else
-  _IDSTACK="$HOME/.claude/plugins/idstack"
+  # Claude Code caches marketplace plugins under a versioned dir; take the
+  # highest version present. Empty if idstack was never installed this way —
+  # every "$_IDSTACK/bin/..." call below is guarded, so that degrades quietly.
+  _IDSTACK=$(ls -d "$HOME"/.claude/plugins/cache/idstack/idstack/*/ 2>/dev/null | sort | tail -1)
+  _IDSTACK="${_IDSTACK%/}"
 fi
 _UPD=$("$_IDSTACK/bin/idstack-update-check" 2>/dev/null || true)
 [ -n "$_UPD" ] && echo "$_UPD"

dist/codex/skills/idstack-course-builder/SKILL.md

@@ -47,14 +47,16 @@ if [ -n "${CLAUDE_PLUGIN_ROOT:-}" ]; then
   _IDSTACK="$CLAUDE_PLUGIN_ROOT"
 elif [ -n "${IDSTACK_HOME:-}" ]; then
   _IDSTACK="$IDSTACK_HOME"
-elif [ -d "$HOME/.claude/plugins/idstack" ]; then
-  _IDSTACK="$HOME/.claude/plugins/idstack"
 elif [ -d "$HOME/.agents/plugins/idstack" ]; then
   _IDSTACK="$HOME/.agents/plugins/idstack"
 elif [ -d "$HOME/.agents/skills/idstack" ]; then
   _IDSTACK="$HOME/.agents/skills/idstack"
 else
-  _IDSTACK="$HOME/.claude/plugins/idstack"
+  # Claude Code caches marketplace plugins under a versioned dir; take the
+  # highest version present. Empty if idstack was never installed this way —
+  # every "$_IDSTACK/bin/..." call below is guarded, so that degrades quietly.
+  _IDSTACK=$(ls -d "$HOME"/.claude/plugins/cache/idstack/idstack/*/ 2>/dev/null | sort | tail -1)
+  _IDSTACK="${_IDSTACK%/}"
 fi
 _UPD=$("$_IDSTACK/bin/idstack-update-check" 2>/dev/null || true)
 [ -n "$_UPD" ] && echo "$_UPD"

dist/codex/skills/idstack-course-export/SKILL.md

@@ -47,14 +47,16 @@ if [ -n "${CLAUDE_PLUGIN_ROOT:-}" ]; then
   _IDSTACK="$CLAUDE_PLUGIN_ROOT"
 elif [ -n "${IDSTACK_HOME:-}" ]; then
   _IDSTACK="$IDSTACK_HOME"
-elif [ -d "$HOME/.claude/plugins/idstack" ]; then
-  _IDSTACK="$HOME/.claude/plugins/idstack"
 elif [ -d "$HOME/.agents/plugins/idstack" ]; then
   _IDSTACK="$HOME/.agents/plugins/idstack"
 elif [ -d "$HOME/.agents/skills/idstack" ]; then
   _IDSTACK="$HOME/.agents/skills/idstack"
 else
-  _IDSTACK="$HOME/.claude/plugins/idstack"
+  # Claude Code caches marketplace plugins under a versioned dir; take the
+  # highest version present. Empty if idstack was never installed this way —
+  # every "$_IDSTACK/bin/..." call below is guarded, so that degrades quietly.
+  _IDSTACK=$(ls -d "$HOME"/.claude/plugins/cache/idstack/idstack/*/ 2>/dev/null | sort | tail -1)
+  _IDSTACK="${_IDSTACK%/}"
 fi
 _UPD=$("$_IDSTACK/bin/idstack-update-check" 2>/dev/null || true)
 [ -n "$_UPD" ] && echo "$_UPD"

dist/codex/skills/idstack-course-import/SKILL.md

@@ -47,14 +47,16 @@ if [ -n "${CLAUDE_PLUGIN_ROOT:-}" ]; then
   _IDSTACK="$CLAUDE_PLUGIN_ROOT"
 elif [ -n "${IDSTACK_HOME:-}" ]; then
   _IDSTACK="$IDSTACK_HOME"
-elif [ -d "$HOME/.claude/plugins/idstack" ]; then
-  _IDSTACK="$HOME/.claude/plugins/idstack"
 elif [ -d "$HOME/.agents/plugins/idstack" ]; then
   _IDSTACK="$HOME/.agents/plugins/idstack"
 elif [ -d "$HOME/.agents/skills/idstack" ]; then
   _IDSTACK="$HOME/.agents/skills/idstack"
 else
-  _IDSTACK="$HOME/.claude/plugins/idstack"
+  # Claude Code caches marketplace plugins under a versioned dir; take the
+  # highest version present. Empty if idstack was never installed this way —
+  # every "$_IDSTACK/bin/..." call below is guarded, so that degrades quietly.
+  _IDSTACK=$(ls -d "$HOME"/.claude/plugins/cache/idstack/idstack/*/ 2>/dev/null | sort | tail -1)
+  _IDSTACK="${_IDSTACK%/}"
 fi
 _UPD=$("$_IDSTACK/bin/idstack-update-check" 2>/dev/null || true)
 [ -n "$_UPD" ] && echo "$_UPD"