Plugin hook error

[jokerping]

/model to try Opus 4.5
⎿  SessionStart:startup says: Plugin hook error: 📝 Claude-Mem Context Loaded
ℹ️ Note: This appears as stderr but is informational only

 [ZWDouyuxingchen] recent context
 ────────────────────────────────────────────────────────────

 No previous sessions found for this project yet.


 💡 New! Wrap all or part of any message with <private> ... </private> to prevent storing sensitive information in your observation history.

 💬 Community https://discord.gg/J4wttp9vDu
 📺 Watch live in browser http://localhost:37777/

Is this a bug? It seems I can't find previous conversations now.

[github-actions]

A user reported encountering a "Plugin hook error" message when running /model to try Opus 4.5, though it appears to be informational rather than an actual error. The session output mentioned no previous sessions were found for the project, and the user noted they can no longer access past conversations. They are unsure if this behavior is a bug and are seeking clarification. Additional context includes references to community resources and developer tools, such as a Discord link and a browser-based live preview.

[jokerping]

. plugin:claude-mem:claude-mem-search ✘ failed · Enter to view details
This mcp error occurred.

I tried letting CC solve the problem itself, and it told me that File ecosystem.config.cjs was not found.

[jokerping]

Problem Diagnosis

1. Conflict with an older worker version: An older version of the claude-mem worker service (from the marketplaces directory) is running on the system, which is incompatible with the new 7.2.3 version.

2. Incorrect startup method: The new version of worker-service.cjs requires running with bun, not node, because it depends on the bun:sqlite module.

Repairs Performed

1. ✅ Terminated the older version of the worker process.

2. ✅ Started the new version (7.2.3) worker service using the correct bun runtime.

3. ✅ Verified that the worker service is in good health.

The worker service is now running normally on port 37777 (process ID: 80102).

Persistence Recommendation

The current worker service is running in the background, but may need to be restarted after a system reboot. To make it persistent, you can:

1. Create a startup script

2. Or add it to PM2 management (if needed)

Now you can try running the /mcp command again, and the MCP service should be able to connect normally.

This is CC's conclusion, but it has no effect.

[paragbaxi]

Reproduced on mac 26.1 Claude Code v2.0.69

  ⎿  SessionStart:startup says: Plugin hook error: 📝 Claude-Mem Context Loaded
        ℹ️  Note: This appears as stderr but is informational only

[iefnaf]

Hi! Thanks for reporting this issue. This is indeed a confusing design choice, so let me explain why this happens.

Root Cause

This "Plugin hook error" message is not actually an error - it's a technical limitation of the Claude Code plugin system.

Why We Use stderr

In user-message-hook.ts, we use console.error for output due to the following reasons:

1. Claude Code Plugin Architecture Limitation

/**
 * Uses stderr as the communication channel
 * since it's currently the only way to display messages in Claude Code UI.
 */

Currently, stderr is the only channel through which Claude Code plugins can display messages to users. stdout output is ignored by the system and doesn't appear in the user interface.

2. Intended User Experience

We want to show users when sessions start:

• 📝 Loaded context information
• 💡 Privacy protection tips (<private> tag usage)
• 📺 Link to the live viewer interface

This information is valuable to users, but can only be delivered through stderr.

3. Temporary Technical Solution

The code explicitly acknowledges this issue:

🎉  Note: This appears under Plugin Hook Error, but it's not an error. That's the only option for
   user messages in Claude Code UI until a better method is provided.

About "No previous sessions found"

Regarding your concern about not finding previous conversations - this is separate from the stderr issue. The "No previous sessions found for this project yet" message means:

• You haven't had any sessions in this specific project directory
• Or the worker service might still be starting up
• This is normal behavior for new projects

You can check if there are any existing sessions by visiting http://localhost:37777/ in your browser.

Future Improvements

We're waiting for Claude Code to provide a better user messaging system, which will allow us to:

• Remove dependency on stderr
• Eliminate the misleading "Plugin hook error" display
• Provide a clearer user experience

Current Behavior

Although it displays as an "error", this:

• ✅ Does not affect plugin functionality
• ✅ Does not impact data storage
• ✅ Is expected behavior

This is a known technical limitation, not a functional issue.

Thanks for your understanding! If you find this display confusing, we also suggest reporting this in Claude Code's feedback channels to help encourage the team to provide better plugin messaging mechanisms.

[iefnaf]

Hey @thedotmack! I saw this issue and wanted to confirm the solution for eliminating the confusing "plugin hook error" message.

Problem Analysis

The user-message-hook.ts was using exit code 3 (USER_MESSAGE_ONLY), which caused Claude Code to display "hook error" messages even though everything was working correctly. This understandably confused users into thinking something was wrong.

Solution

According to the Claude Code hooks documentation, we can use exit code 0 with a JSON systemMessage field to display information to users without showing it as an error.

Great to see this fix has been confirmed as working by users in the thread! This makes the user experience much cleaner by removing the false error messages.

Impact

• ✅ Users no longer see confusing "hook error" messages
• ✅ Context information still displays normally to users
• ✅ No impact on context-hook functionality
• ✅ Follows Claude Code best practices

I was hoping to help resolve this bug and would be happy to submit a PR if needed. Thanks for the quick work on this improvement! 🎉

[jokerping]

Hi! Thanks for reporting this issue. This is indeed a confusing design choice, so let me explain why this happens.

Root Cause

This "Plugin hook error" message is not actually an error - it's a technical limitation of the Claude Code plugin system.

Why We Use stderr

In user-message-hook.ts, we use console.error for output due to the following reasons:

1. Claude Code Plugin Architecture Limitation

/**

• Uses stderr as the communication channel
• since it's currently the only way to display messages in Claude Code UI.
  */
  Currently, stderr is the only channel through which Claude Code plugins can display messages to users. stdout output is ignored by the system and doesn't appear in the user interface.

2. Intended User Experience

We want to show users when sessions start:

• 📝 Loaded context information
• 💡 Privacy protection tips (<private> tag usage)
• 📺 Link to the live viewer interface

This information is valuable to users, but can only be delivered through stderr.

3. Temporary Technical Solution

The code explicitly acknowledges this issue:

🎉  Note: This appears under Plugin Hook Error, but it's not an error. That's the only option for
   user messages in Claude Code UI until a better method is provided.

About "No previous sessions found"

Regarding your concern about not finding previous conversations - this is separate from the stderr issue. The "No previous sessions found for this project yet" message means:

• You haven't had any sessions in this specific project directory
• Or the worker service might still be starting up
• This is normal behavior for new projects

You can check if there are any existing sessions by visiting http://localhost:37777/ in your browser.

Future Improvements

We're waiting for Claude Code to provide a better user messaging system, which will allow us to:

• Remove dependency on stderr
• Eliminate the misleading "Plugin hook error" display
• Provide a clearer user experience

Current Behavior

Although it displays as an "error", this:

• ✅ Does not affect plugin functionality
• ✅ Does not impact data storage
• ✅ Is expected behavior

This is a known technical limitation, not a functional issue.

Thanks for your understanding! If you find this display confusing, we also suggest reporting this in Claude Code's feedback channels to help encourage the team to provide better plugin messaging mechanisms.

Yes, I can see the historical prompts at 37777, but currently mcp claude-mem-search is failing. Is this a problem?

[jokerping]

Hi! Thanks for reporting this issue. This is indeed a confusing design choice, so let me explain why this happens.

Root Cause

This "Plugin hook error" message is not actually an error - it's a technical limitation of the Claude Code plugin system.

Why We Use stderr

In user-message-hook.ts, we use console.error for output due to the following reasons:

1. Claude Code Plugin Architecture Limitation

/**

• Uses stderr as the communication channel
• since it's currently the only way to display messages in Claude Code UI.
  */
  Currently, stderr is the only channel through which Claude Code plugins can display messages to users. stdout output is ignored by the system and doesn't appear in the user interface.

2. Intended User Experience

We want to show users when sessions start:

• 📝 Loaded context information
• 💡 Privacy protection tips (<private> tag usage)
• 📺 Link to the live viewer interface

This information is valuable to users, but can only be delivered through stderr.

3. Temporary Technical Solution

The code explicitly acknowledges this issue:

🎉  Note: This appears under Plugin Hook Error, but it's not an error. That's the only option for
   user messages in Claude Code UI until a better method is provided.

About "No previous sessions found"

Regarding your concern about not finding previous conversations - this is separate from the stderr issue. The "No previous sessions found for this project yet" message means:

• You haven't had any sessions in this specific project directory
• Or the worker service might still be starting up
• This is normal behavior for new projects

You can check if there are any existing sessions by visiting http://localhost:37777/ in your browser.

Future Improvements

We're waiting for Claude Code to provide a better user messaging system, which will allow us to:

• Remove dependency on stderr
• Eliminate the misleading "Plugin hook error" display
• Provide a clearer user experience

Current Behavior

Although it displays as an "error", this:

• ✅ Does not affect plugin functionality
• ✅ Does not impact data storage
• ✅ Is expected behavior

This is a known technical limitation, not a functional issue.
Thanks for your understanding! If you find this display confusing, we also suggest reporting this in Claude Code's feedback channels to help encourage the team to provide better plugin messaging mechanisms.

Yes, I can see the historical prompts at 37777, but currently mcp claude-mem-search is failing. Is this a problem?

I solved it using this link.#326 (comment)
The plugin did not install Bun automatically; I installed Bun myself.