diff --git a/README.md b/README.md
index d20463c..9048b38 100644
--- a/README.md
+++ b/README.md
@@ -27,6 +27,20 @@ npm run check
 The repository is an npm workspace. The root package is private; each package
 under [`packages/`](packages) is independently publishable.
 
+### Isolated Pi test
+
+Validate or drive the complete monorepo without loading or changing live Pi
+configuration:
+
+```bash
+scripts/isolated-pi.sh --check
+scripts/isolated-pi.sh
+```
+
+The launcher creates a temporary HOME, copies the current Pi auth and optional
+keybindings files with mode `600`, loads only this local package, and deletes
+the sandbox on exit.
+
 ## License
 
 The root [MIT license](LICENSE) covers Iury-owned packages. `pi-ext` and
diff --git a/scripts/check-isolated-pi.mjs b/scripts/check-isolated-pi.mjs
new file mode 100755
index 0000000..5f4db1c
--- /dev/null
+++ b/scripts/check-isolated-pi.mjs
@@ -0,0 +1,55 @@
+#!/usr/bin/env node
+import fs from "node:fs";
+import path from "node:path";
+import { DefaultResourceLoader, SettingsManager } from "@earendil-works/pi-coding-agent";
+
+const repoRoot = fs.realpathSync(process.argv[2] || ".");
+const cwd = fs.realpathSync(process.argv[3] || process.cwd());
+const agentDir = process.env.PI_CODING_AGENT_DIR;
+
+if (!agentDir) throw new Error("PI_CODING_AGENT_DIR is required");
+
+const manifest = JSON.parse(fs.readFileSync(path.join(repoRoot, "package.json"), "utf8"));
+const settingsManager = SettingsManager.create(cwd, agentDir);
+const loader = new DefaultResourceLoader({
+  cwd,
+  agentDir,
+  settingsManager,
+  noContextFiles: true,
+});
+
+await loader.reload();
+
+const loaded = loader.getExtensions();
+const skills = loader.getSkills();
+const themes = loader.getThemes();
+const diagnostics = [...skills.diagnostics, ...loader.getPrompts().diagnostics, ...themes.diagnostics]
+  .filter((item) => item.type === "error" || item.type === "collision");
+const failures = [];
+
+for (const error of loaded.errors) failures.push(`${error.path}: ${error.error}`);
+for (const diagnostic of diagnostics) failures.push(`${diagnostic.path || "resource"}: ${diagnostic.message}`);
+
+if (loaded.extensions.length !== manifest.pi.extensions.length) {
+  failures.push(`expected ${manifest.pi.extensions.length} extensions, loaded ${loaded.extensions.length}`);
+}
+
+for (const extension of loaded.extensions) {
+  const relative = path.relative(repoRoot, fs.realpathSync(extension.resolvedPath));
+  if (!relative || relative.startsWith("..") || path.isAbsolute(relative)) {
+    failures.push(`extension loaded outside monorepo: ${extension.resolvedPath}`);
+  }
+}
+
+if (skills.skills.length !== manifest.pi.skills.length) {
+  failures.push(`expected ${manifest.pi.skills.length} skills, loaded ${skills.skills.length}`);
+}
+
+if (failures.length > 0) {
+  throw new Error(`Isolated Pi check failed:\n- ${failures.join("\n- ")}`);
+}
+
+console.log("Isolated Pi check passed.");
+console.log(`Extensions: ${loaded.extensions.length}`);
+console.log(`Skills: ${skills.skills.map((skill) => skill.name).sort().join(", ")}`);
+console.log(`Themes: ${themes.themes.length}`);
diff --git a/scripts/isolated-pi.sh b/scripts/isolated-pi.sh
new file mode 100755
index 0000000..7c025a8
--- /dev/null
+++ b/scripts/isolated-pi.sh
@@ -0,0 +1,99 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+root="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd -P)"
+real_home="${HOME:?HOME is required}"
+mode="tui"
+
+case "${1:-}" in
+  --check)
+    mode="check"
+    shift
+    ;;
+  --help|-h)
+    cat <<'EOF'
+Usage: scripts/isolated-pi.sh [--check] [pi arguments...]
+
+Without --check, starts an interactive Pi TUI with only this monorepo loaded.
+The temporary HOME, copied auth, settings, sessions, and workspace are deleted
+when the command exits.
+EOF
+    exit 0
+    ;;
+esac
+
+for command in jq node pi; do
+  if ! command -v "$command" >/dev/null 2>&1; then
+    printf 'Missing required command: %s\n' "$command" >&2
+    exit 1
+  fi
+done
+
+live_agent_dir="$real_home/.pi/agent"
+live_settings="$live_agent_dir/settings.json"
+live_auth="$live_agent_dir/auth.json"
+live_keybindings="$live_agent_dir/keybindings.json"
+
+if [[ ! -f "$live_settings" ]]; then
+  printf 'Missing live Pi settings: %s\n' "$live_settings" >&2
+  exit 1
+fi
+if [[ ! -f "$live_auth" ]]; then
+  printf 'Missing live Pi auth: %s\n' "$live_auth" >&2
+  exit 1
+fi
+
+sandbox="$(mktemp -d "${TMPDIR:-/tmp}/pi-extensions-isolated.XXXXXX")"
+cleanup() {
+  chmod -R u+w "$sandbox" 2>/dev/null || true
+  rm -rf "$sandbox"
+}
+trap cleanup EXIT
+
+sandbox_home="$sandbox/home"
+agent_dir="$sandbox_home/.pi/agent"
+workspace="$sandbox/workspace"
+mkdir -p "$agent_dir" "$workspace" \
+  "$sandbox_home/.cache" \
+  "$sandbox_home/.config" \
+  "$sandbox_home/.local/share" \
+  "$sandbox_home/.local/state"
+install -m 600 "$live_auth" "$agent_dir/auth.json"
+if [[ -f "$live_keybindings" ]]; then
+  install -m 600 "$live_keybindings" "$agent_dir/keybindings.json"
+fi
+
+jq --arg source "$root" '
+  {
+    packages: [{ source: $source }],
+    defaultProvider,
+    defaultModel,
+    defaultThinkingLevel,
+    theme,
+    hideThinkingBlock,
+    quietStartup,
+    transport,
+    lastChangelogVersion
+  }
+  | with_entries(select(.value != null))
+' "$live_settings" > "$agent_dir/settings.json"
+chmod 600 "$agent_dir/settings.json"
+
+sandbox_env=(
+  "HOME=$sandbox_home"
+  "PI_CODING_AGENT_DIR=$agent_dir"
+  "XDG_CACHE_HOME=$sandbox_home/.cache"
+  "XDG_CONFIG_HOME=$sandbox_home/.config"
+  "XDG_DATA_HOME=$sandbox_home/.local/share"
+  "XDG_STATE_HOME=$sandbox_home/.local/state"
+)
+
+printf 'Isolated package: %s\n' "$root"
+printf 'Disposable HOME: %s\n' "$sandbox_home"
+
+if [[ "$mode" == "check" ]]; then
+  env "${sandbox_env[@]}" node "$root/scripts/check-isolated-pi.mjs" "$root" "$workspace"
+else
+  cd "$workspace"
+  env "${sandbox_env[@]}" pi --no-context-files "$@"
+fi