Five Whys MCP Server

A Model Context Protocol (MCP) server that implements the 5 Whys methodology for systematic root cause analysis. This tool helps developers and problem-solvers identify the root cause of issues through structured questioning.

What is the 5 Whys Methodology?

The 5 Whys is a problem-solving technique that involves asking "why" repeatedly (typically 5 times) to drill down to the root cause of a problem. It's particularly effective for:

• Debugging complex software issues
• Understanding system failures
• Identifying process bottlenecks
• Analyzing user experience problems
• Investigating production incidents

Features

• Interactive Analysis: Guides you through the 5 Whys process step by step
• State Management: Maintains analysis state across multiple interactions
• Multiple Export Formats: Export results as Markdown, JSON, or plain text
• Root Cause Identification: Automatically identifies the root cause after completion
• Reset & Restart: Easily start fresh analyses
• MCP Integration: Works seamlessly with Claude and other MCP-compatible tools

Installation

Prerequisites

• Node.js 18 or higher
• npm or yarn

Install the Package

npm install five-whys-mcp-server

Add to Claude Code

Option 1: Automatic Installation (Recommended)

Use the Claude CLI command to add the server automatically:

claude mcp add five-whys npx five-whys-mcp-server # For local installation
claude mcp add -s user five-whys npx five-whys-mcp-server # user scope

This command will:

• Add the server to your Claude configuration
• No manual file editing required
• Works with both Claude Desktop and Claude Code

Option 2: Manual Installation

1. Open your Claude Desktop configuration file:

   • macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
   • Windows: %APPDATA%/Claude/claude_desktop_config.json

2. Add the server configuration:

{
  "mcpServers": {
    "five-whys": {
      "command": "npx",
      "args": ["five-whys-mcp-server"]
    }
  }
}

3. Restart Claude Desktop

Usage

Once installed and configured, you can use the following tools in Claude Code:

1. Start a New Analysis

Ask Claude to start a 5 whys analysis with your problem statement:

Claude Code Examples:

"Start a 5 whys analysis for: The website is loading slowly for users"

"Help me analyze why our CI/CD pipeline keeps failing"

"I need to do a root cause analysis on this bug: Users can't log in after the latest update"

What happens:

• Claude will use the start_five_whys tool
• You'll get the first "why" question to answer
• The analysis session begins

2. Answer Why Questions

Respond naturally to Claude's "why" questions during the analysis:

Claude Code Examples:

"The database queries are taking too long"

"Because there are no indexes on the user_activity table"

"The development team didn't know about indexing best practices"

What happens:

• Claude uses the answer_why tool with your response
• You get the next "why" question automatically
• Progress is tracked (e.g., "Question 2/5")

3. Check Current State

Ask Claude to show your current progress:

Claude Code Examples:

"Show me the current state of my 5 whys analysis"

"What's my progress on the root cause analysis?"

"Can you display where we are in the analysis?"

What happens:

• Claude uses the get_current_state tool
• You see all questions and answers so far
• Current progress and next steps are displayed

4. Export Results

Request your complete analysis in different formats:

Claude Code Examples:

"Export my 5 whys analysis as markdown"

"Give me the analysis results in JSON format"

"Can you export this as a text summary I can share with my team?"

Available formats:

• markdown - Rich formatted document (default)
• json - Structured data format
• text - Plain text summary

What happens:

• Claude uses the export_analysis tool
• You get a complete formatted report
• Perfect for documentation or sharing

5. Reset Analysis

Start fresh when needed:

Claude Code Examples:

"Reset the current analysis, I want to start over"

"Clear this analysis and let me begin with a new problem"

"Start fresh - I need to analyze a different issue"

What happens:

• Claude uses the reset_analysis tool
• All current progress is cleared
• You can immediately start a new analysis

Complete Workflow Example

Here's how a typical session with Claude Code looks:

You: "Start a 5 whys analysis for: The website is loading slowly for users"

Claude: ✅ Analysis started successfully. Please answer the first 'why' question.

Current Analysis:

• Problem: The website is loading slowly for users
• Status: In Progress
• Progress: 1/5 questions

Next Question: Why did this problem occur?

You: "The database queries are taking too long"

Claude: ✅ Answer recorded. Please answer the next 'why' question (2/5).

Questions & Answers:

1. Why did this problem occur? → The database queries are taking too long

Next Question: Why did this happen?

You: "There are no indexes on frequently queried columns"

Claude: ✅ Answer recorded. Please answer the next 'why' question (3/5).

[continues until completion]

You: "Export this analysis as markdown"

Claude: [provides complete formatted analysis]

Example Analysis Session

1. Problem: "The website is loading slowly for users"
   
2. Why is the website loading slowly?
   → The database queries are taking too long
   
3. Why are the database queries taking too long?
   → There are no indexes on frequently queried columns
   
4. Why are there no indexes on frequently queried columns?
   → The database was not properly optimized during development
   
5. Why was the database not properly optimized during development?
   → There was no database performance review in the development process
   
6. Why was there no database performance review in the development process?
   → The development team lacks database optimization expertise

Root Cause: The development team lacks database optimization expertise

Available Tools

| Tool | Description | Parameters | |------|-------------|------------| | start_five_whys | Begin a new analysis | problem: string | | answer_why | Answer current question | answer: string | | get_current_state | Get analysis status | none | | export_analysis | Export results | format?: 'markdown' \| 'json' \| 'text' | | reset_analysis | Reset current analysis | none |

Development

Local Development

1. Clone the repository
2. Install dependencies: npm install
3. Build the project: npm run build
4. Start development mode: npm run dev

Testing

To test the MCP server locally:

# Start the server
npm start

# In another terminal, test with MCP inspector
npx @modelcontextprotocol/inspector http://localhost:3000

Configuration

The server runs on stdio transport by default, which is suitable for MCP integration. No additional configuration is required.

Troubleshooting

Common Issues

1. Server not starting: Ensure Node.js 18+ is installed
2. Tools not appearing in Claude: Check the configuration file path and restart Claude
3. Permission errors: Make sure the package has execute permissions

Debug Mode

To run with debug output:

DEBUG=* npx five-whys-mcp-server

Contributing

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Add tests if applicable
5. Submit a pull request

License

MIT License - see LICENSE file for details

Support

For issues and questions:

• Open an issue on GitHub
• Check the troubleshooting section
• Review the MCP documentation

Built with the Model Context Protocol (MCP) for seamless integration with AI assistants.