feat: custom debug java agent

README.md

@@ -17,6 +17,8 @@ A lightweight Java Debugger based on [Java Debug Server](https://github.com/Micr
 - Debug console
 - Evaluation
 - Hot Code Replace
+- No-Config Debug (debug Java apps without launch.json)
+- **[AI]** AI-Assisted Debugging (GitHub Copilot integration)
 
 ## Requirements
 - JDK (version 1.8.0 or later)
@@ -41,6 +43,38 @@ ext install vscode-java-debug
 
 Please also check the documentation of [Language Support for Java by Red Hat](https://marketplace.visualstudio.com/items?itemName=redhat.java) if you have trouble setting up your project.
 
+## No-Config Debug
+
+You can now debug Java applications without creating a `launch.json` file! Simply open a terminal in VS Code and use the `debugjava` command:
+
+```bash
+# Debug a main class
+debugjava -cp bin com.example.Main
+
+# Debug a JAR file
+debugjava -jar target/myapp.jar
+
+# Debug with arguments
+debugjava -cp bin com.example.Main arg1 arg2
+```
+
+The debugger will automatically attach. See [No-Config Debug Documentation](bundled/scripts/noConfigScripts/README.md) for more details.
+
+## AI-Assisted Debugging
+
+When using GitHub Copilot Chat, you can now ask AI to help you debug Java applications! The extension provides a Language Model Tool that enables natural language debugging:
+
+- "Debug my Spring Boot application"
+- "Debug the Main class in this project"
+- "Debug Calculator with arguments 10 and 5"
+
+The AI will automatically:
+1. Detect your project type (Maven/Gradle/VS Code)
+2. Build/compile your project
+3. Start debugging with appropriate configuration
+
+See [Language Model Tool Documentation](bundled/agents/README.md) for more details.
+
 ## Options
 
 ### Launch

bundled/agents/README.md

@@ -0,0 +1,195 @@
+# Java Debug Agent
+
+The Java Debug Agent is an AI-powered debugging assistant that integrates with GitHub Copilot Chat to help you debug Java applications using natural language.
+
+## Overview
+
+Instead of manually setting breakpoints and inspecting variables, you can simply describe your debugging task in natural language. The agent will:
+
+1. Analyze your code to form hypotheses
+2. Set targeted breakpoints
+3. Inspect variables and evaluate expressions
+4. Find the root cause of bugs
+
+## Requirements
+
+- VS Code 1.95.0 or later
+- [Language Support for Java by Red Hat](https://marketplace.visualstudio.com/items?itemName=redhat.java)
+- [Debugger for Java](https://marketplace.visualstudio.com/items?itemName=vscjava.vscode-java-debug)
+- GitHub Copilot Chat extension
+
+## Getting Started
+
+### 1. Open Copilot Chat
+
+Press `Ctrl+Shift+I` (Windows/Linux) or `Cmd+Shift+I` (macOS) to open Copilot Chat.
+
+### 2. Switch to JavaDebug Agent Mode
+
+In the Copilot Chat panel, click on the agent selector (usually shows "Copilot" or current agent name) and select **JavaDebug** from the dropdown list.
+
+![Select Agent](images/javadebug.png)
+<!-- TODO: Add screenshot showing agent selector dropdown -->
+
+### 3. Enter Your Debugging Request
+
+Once in JavaDebug mode, simply type your debugging request:
+
+```
+Why am I getting a NullPointerException in OrderService?
+```
+
+![Invoke Agent](images/invoke-agent.png)
+<!-- TODO: Add screenshot showing chat input -->
+
+### 4. Let the Agent Work
+
+The agent will:
+- Read relevant code files
+- Form a hypothesis about the bug
+- Set breakpoints at strategic locations
+- Start or attach to a debug session
+- Inspect variables to verify the hypothesis
+- Report the root cause
+
+![Agent Working](images/agent-working.png)
+<!-- TODO: Add screenshot showing agent analyzing code -->
+
+## Example Usage
+
+### Debug a NullPointerException
+
+```
+I'm getting NPE when calling userService.getUser()
+```
+
+The agent will:
+1. Read `UserService.java`
+2. Hypothesize which variable might be null
+3. Set a breakpoint before the NPE
+4. Check variable values
+5. Report: "The `user` variable is null because `findById()` returns null when ID doesn't exist"
+
+### Debug Wrong Calculation Result
+
+```
+The calculateTotal() method returns wrong value
+```
+
+### Debug with Specific Input
+
+```
+Debug processOrder with orderId=456
+```
+
+### Debug Multi-threaded Issues
+
+```
+I suspect a race condition in the worker threads
+```
+
+## Agent Capabilities
+
+| Capability | Description |
+|------------|-------------|
+| **Start Debug Session** | Launch or attach to Java applications |
+| **Set Breakpoints** | Set conditional or unconditional breakpoints |
+| **Inspect Variables** | View local variables, fields, and objects |
+| **Evaluate Expressions** | Execute Java expressions in debug context |
+| **Step Through Code** | Step over, step into, step out |
+| **Multi-thread Support** | Debug concurrent applications |
+| **Stack Trace Analysis** | View and navigate call stacks |
+
+## How It Works
+
+The agent uses **hypothesis-driven debugging**:
+
+```
+┌─────────────────────────────────────────┐
+│  1. STATIC ANALYSIS                     │
+│     Read code, understand the problem   │
+└─────────────────┬───────────────────────┘
+                  ↓
+┌─────────────────────────────────────────┐
+│  2. FORM HYPOTHESIS                     │
+│     "Variable X is null at line Y"      │
+└─────────────────┬───────────────────────┘
+                  ↓
+┌─────────────────────────────────────────┐
+│  3. SET BREAKPOINT                      │
+│     At the location to verify           │
+└─────────────────┬───────────────────────┘
+                  ↓
+┌─────────────────────────────────────────┐
+│  4. VERIFY                              │
+│     Check if hypothesis is correct      │
+│     ├─ YES → Report root cause          │
+│     └─ NO  → Form new hypothesis        │
+└─────────────────────────────────────────┘
+```
+
+## Tips for Best Results
+
+### Stay in Agent Mode
+
+Make sure you're in **JavaDebug** agent mode (check the agent selector in Chat panel). If you switch back to default Copilot mode, the debugging tools won't be available.
+
+### Be Specific
+
+```
+✅ Good: "Why does getUserById return null when id=123?"
+❌ Vague: "Something is wrong"
+```
+
+### Mention the Error
+
+```
+✅ Good: "Getting ArrayIndexOutOfBoundsException in processItems()"
+❌ Vague: "Debug processItems"
+```
+
+### Provide Context
+
+```
+✅ Good: "The order total is $0 instead of $150 for order 456"
+❌ Vague: "Wrong calculation"
+```
+
+## Troubleshooting
+
+### Agent Can't Find the File
+
+Make sure the Java project is properly loaded. Check that:
+- The Java extension is activated (look for Java icon in status bar)
+- The project is imported (check Java Projects view)
+
+### Debug Session Won't Start
+
+Ensure:
+- Your project compiles successfully
+- No other debug session is running
+- The main class can be found
+
+### Breakpoint Not Hit
+
+The agent will tell you to trigger the scenario. You need to:
+1. Run the part of your application that executes the code
+2. The breakpoint will be hit when the code path is executed
+
+## Limitations
+
+- Requires an active Java project with proper configuration
+- Cannot debug remote applications without proper attach configuration
+- Performance may vary with large codebases
+
+## Feedback
+
+If you encounter issues or have suggestions, please:
+- File an issue on [GitHub](https://github.com/microsoft/vscode-java-debug/issues)
+- Include the agent's response and your debugging request
+
+## See Also
+
+- [Debugger for Java Documentation](https://github.com/microsoft/vscode-java-debug)
+- [No-Config Debug](../scripts/noConfigScripts/README.md)
+- [Troubleshooting Guide](../../Troubleshooting.md)