Fix SessionStart hook variable expansion on Linux

[04cb]

Fixes issue #577. The hook command used single quotes around CLAUDE_PLUGIN_ROOT which prevented shell variable expansion on Linux. This caused the hook to fail with No such file or directory error.

Changed from single quotes to no quotes since the JSON string already provides proper quoting. The shell will now correctly expand the CLAUDE_PLUGIN_ROOT environment variable.

[coderabbitai]

📝 Walkthrough

Walkthrough

The change modifies the hooks.json configuration file by removing outer single quotes from a command string and restructuring argument placement. The SessionStart hook command is updated to pass the session-start argument as part of the same string rather than as a separate quoted element.

Changes

Cohort / File(s)	Summary
Configuration Update hooks/hooks.json	Modified SessionStart hook command: removed outer single quotes and reorganized argument positioning for run-hook.cmd session-start invocation.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~2 minutes

Possibly related issues

• SessionStart hook fails on Windows: CLAUDE_PLUGIN_ROOT backslashes mangled by bash #487: Addresses the same hooks.json SessionStart command string modification concerning ${CLAUDE_PLUGIN_ROOT} path and bash execution on Windows.
• SessionStart hook fails on Linux: CLAUDE_PLUGIN_ROOT not expanding #577: Directly related to fixing shell variable expansion of ${CLAUDE_PLUGIN_ROOT} in the hooks.json command string.
• Windows: SessionStart hook fails due to CLAUDE_PLUGIN_ROOT path handling #399: Modifies the same hooks.json SessionStart hook command entry formatting.
• SessionStart hook fails on Windows — bash cannot resolve ${CLAUDE_PLUGIN_ROOT} path #389: Affects the same hooks.json session-start hook command quoting and structure.
• SessionStart hook fails on Windows when user profile path contains spaces #518: Related to the hooks.json command string modification affecting ${CLAUDE_PLUGIN_ROOT} path parsing.

Possibly related PRs

• Add Windows support for plugin hooks #134: Modifies the same hooks/hooks.json command invocation for run-hook.cmd/session-start with quoting and argument adjustments.
• fix: restore polyglot wrapper for Windows hook compatibility (4.3.1) #523: Updates the same hooks.json SessionStart command entry with restructured quoting and argument placement.

Poem

🐰 Quotes around paths causing quite the fuss,
A rabbit removes them without making a fuss,
Now the argument flows in one gleaming stream,
Session-start runs smoother than ever—a dream! 🌟

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and specifically identifies the main change: fixing variable expansion for the SessionStart hook on Linux systems.
Description check	✅ Passed	The description is directly related to the changeset, explaining the issue being fixed, the root cause, and the solution applied.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

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✨ Finishing Touches

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@hooks/hooks.json`:
- Line 9: The command value in hooks.json currently interpolates
${CLAUDE_PLUGIN_ROOT}/hooks/run-hook.cmd without quotes, which breaks on Windows
paths with spaces; update the "command" entry so the executable path portion is
wrapped in double quotes while leaving the session-start argument unquoted
(i.e., quote ${CLAUDE_PLUGIN_ROOT}/hooks/run-hook.cmd but keep session-start as
a separate argument) so the "command" key correctly handles paths with spaces.

---

ℹ️ Review info

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between e4a2375 and 5dcb888.

📒 Files selected for processing (1)

• hooks/hooks.json

[coderabbitai]

⚠️ Potential issue | 🟠 Major

🧩 Analysis chain

🏁 Script executed:

fd hooks.json -x cat -n {}

Repository: obra/superpowers

Length of output: 479

---

🏁 Script executed:

# Look for other hook commands to see if there's a consistent pattern
rg "command.*CLAUDE_PLUGIN_ROOT" -A 2 -B 2

Repository: obra/superpowers

Length of output: 1225

---

🏁 Script executed:

# Search for any documentation or comments about variable expansion in hooks
rg -i "variable.*expansion|quote|CLAUDE_PLUGIN_ROOT" --type json --type md --type txt

Repository: obra/superpowers

Length of output: 1318

---

🏁 Script executed:

# Check if there are any other similar configuration patterns in the repo
fd -e json -x grep -l "CLAUDE_PLUGIN_ROOT" {}

Repository: obra/superpowers

Length of output: 78

---

Missing quotes around path variable will break Windows installations with spaces in the plugin directory.

The documentation in docs/windows/polyglot-hooks.md explicitly requires quoting: "The path must be quoted because ${CLAUDE_PLUGIN_ROOT} may contain spaces on Windows (e.g., C:\Program Files\...)." All examples in that file use double quotes around the variable expansion.

Change to:

Diff

-            "command": "${CLAUDE_PLUGIN_ROOT}/hooks/run-hook.cmd session-start",
+            "command": "\"${CLAUDE_PLUGIN_ROOT}/hooks/run-hook.cmd\" session-start",

📝 Committable suggestion

‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.

Suggested change

	"command": "${CLAUDE_PLUGIN_ROOT}/hooks/run-hook.cmd session-start",
	"command": "\"${CLAUDE_PLUGIN_ROOT}/hooks/run-hook.cmd\" session-start",

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@hooks/hooks.json` at line 9, The command value in hooks.json currently
interpolates ${CLAUDE_PLUGIN_ROOT}/hooks/run-hook.cmd without quotes, which
breaks on Windows paths with spaces; update the "command" entry so the
executable path portion is wrapped in double quotes while leaving the
session-start argument unquoted (i.e., quote
${CLAUDE_PLUGIN_ROOT}/hooks/run-hook.cmd but keep session-start as a separate
argument) so the "command" key correctly handles paths with spaces.

[Jamie-Clayton]

I've been having similar issues loading superpowers as @04cb . I've tried both the fix submitted and the CodeRabbit.

Test environment

• Claude Code v2.1.50
• SuperPowers v4.3.1 (installed from claude /plugin)

I've also tried to get Claude to interactively try and resolve the issue with no luck. The issue seems to be triggered by running multiple Claude Code sessions in different terminal windows, in my situation.

Claude Code change log suggests there is some bug fixes in a newer version.

v2.1.61 — Fixed concurrent writes corrupting config on Windows. This is almost certainly contributing to your inconsistent plugin loading, since plugin state is tracked in config files that can corrupt under concurrent access.

Initial testing with Claude Code v2.1.61 looks promising.

Root cause summary for the PR comment: the fix that actually worked on Windows with v2.1.63 was:

1. Remove single-quotes from the command (fix variable expansion — the Linux bug in SessionStart hook fails on Linux: CLAUDE_PLUGIN_ROOT not expanding #577)
2. Use .sh extension so Claude Code's auto-detection invokes bash correctly
3. Remove the additional_context top-level field from the JSON output