diff --git a/.codex-plugin/plugin.json b/.codex-plugin/plugin.json
index 166b797..d78cda5 100644
--- a/.codex-plugin/plugin.json
+++ b/.codex-plugin/plugin.json
@@ -1,6 +1,6 @@
 {
     "name": "propulsion",
-    "version": "1.0.4",
+    "version": "1.0.5",
     "description": "Opinionated agentic coding workflow that guides software work from exploration and planning through execution and review.",
     "author": {
         "name": "Moon Pixels"
diff --git a/hooks/hooks.json b/hooks/hooks.json
index ef959fa..499e20f 100644
--- a/hooks/hooks.json
+++ b/hooks/hooks.json
@@ -6,7 +6,7 @@
                 "hooks": [
                     {
                         "type": "command",
-                        "command": "\"${CODEX_PLUGIN_ROOT}/hooks/run-hook.cmd\" session-start",
+                        "command": "\"${CODEX_PLUGIN_ROOT:-${CLAUDE_PLUGIN_ROOT:-}}/hooks/run-hook.cmd\" session-start",
                         "timeout": 10,
                         "statusMessage": "Loading Propulsion workflow"
                     }
diff --git a/package.json b/package.json
index 06e1d4c..50a5a29 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
     "name": "propulsion",
-    "version": "1.0.4",
+    "version": "1.0.5",
     "main": "./index.mjs",
     "exports": "./index.mjs",
     "scripts": {
diff --git a/skills/pr/SKILL.md b/skills/pr/SKILL.md
index 4d6141a..fa173ab 100644
--- a/skills/pr/SKILL.md
+++ b/skills/pr/SKILL.md
@@ -11,7 +11,7 @@ Create or reuse one GitHub pull request from the current branch and report the v
 
 ALL prerequisites MUST be true before following this skill.
 
-- GitHub CLI `gh` is installed and authenticated for the target repository.
+- GitHub CLI `gh` is installed and authenticated for the target repository (may need to run outside sandbox).
 - The current directory is a git repository with an `origin` remote.
 
 ## Instructions
diff --git a/tests/codex-hook.test.js b/tests/codex-hook.test.js
index ca70fab..a2cbad0 100644
--- a/tests/codex-hook.test.js
+++ b/tests/codex-hook.test.js
@@ -10,6 +10,27 @@ async function readJson(path) {
     return JSON.parse(await readFile(path, 'utf8'));
 }
 
+async function runConfiguredHook(env) {
+    const config = await readJson('hooks/hooks.json');
+    const command = config.hooks.SessionStart[0].hooks[0].command;
+
+    const result = Bun.spawnSync({
+        cmd: ['sh', '-c', command],
+        cwd: '/private/tmp',
+        env: {
+            ...process.env,
+            ...env,
+        },
+        stdout: 'pipe',
+        stderr: 'pipe',
+    });
+
+    expect(result.exitCode).toBe(0);
+
+    const output = new TextDecoder().decode(result.stdout).trim();
+    return JSON.parse(output);
+}
+
 describe('Codex Propulsion bootstrap guidance', () => {
     test('uses the shared Propulsion bootstrap contract', () => {
         expect(getPropulsionBootstrapGuidance()).toBe(
@@ -27,7 +48,7 @@ describe('Codex Propulsion bootstrap guidance', () => {
                     {
                         type: 'command',
                         command:
-                            '"${CODEX_PLUGIN_ROOT}/hooks/run-hook.cmd" session-start',
+                            '"${CODEX_PLUGIN_ROOT:-${CLAUDE_PLUGIN_ROOT:-}}/hooks/run-hook.cmd" session-start',
                         timeout: 10,
                         statusMessage: 'Loading Propulsion workflow',
                     },
@@ -36,25 +57,22 @@ describe('Codex Propulsion bootstrap guidance', () => {
         ]);
     });
 
-    test('runs configured hook command from outside the plugin cwd', async () => {
-        const config = await readJson('hooks/hooks.json');
-        const command = config.hooks.SessionStart[0].hooks[0].command;
-
-        const result = Bun.spawnSync({
-            cmd: ['sh', '-c', command],
-            cwd: '/private/tmp',
-            env: {
-                ...process.env,
-                CODEX_PLUGIN_ROOT: process.cwd(),
-            },
-            stdout: 'pipe',
-            stderr: 'pipe',
+    test('runs configured hook command with CODEX_PLUGIN_ROOT', async () => {
+        const payload = await runConfiguredHook({
+            CODEX_PLUGIN_ROOT: process.cwd(),
         });
 
-        expect(result.exitCode).toBe(0);
+        expect(payload.hookSpecificOutput).toEqual({
+            hookEventName: 'SessionStart',
+            additionalContext: PROPULSION_BOOTSTRAP_GUIDANCE,
+        });
+    });
 
-        const output = new TextDecoder().decode(result.stdout).trim();
-        const payload = JSON.parse(output);
+    test('runs configured hook command with CLAUDE_PLUGIN_ROOT fallback', async () => {
+        const payload = await runConfiguredHook({
+            CODEX_PLUGIN_ROOT: '',
+            CLAUDE_PLUGIN_ROOT: process.cwd(),
+        });
 
         expect(payload.hookSpecificOutput).toEqual({
             hookEventName: 'SessionStart',