What is Dlv Mcp

dlv-mcp is an MCP Server that integrates with Golang’s Delve Debugger, enabling AI assistants to debug Go applications effectively.

Use cases

Use cases for dlv-mcp include debugging Go applications, automating debugging tasks with AI, and providing interactive debugging capabilities for development teams.

How to use

To use dlv-mcp, start the MCP server with the command ‘dlv-mcp --listen :9097’. Configure your MCP client to connect to ‘http://localhost:9097/sse’ and utilize the available tools for debugging.

Key features

Key features include starting debug sessions, setting breakpoints, stepping through code, evaluating expressions, inspecting variables and stack traces, and managing multiple debug sessions.

Where to use

dlv-mcp can be used in software development environments where Go applications are being developed, particularly for debugging and testing purposes.

Go Delve Debugger MCP Server

An MCP server that allows LLMs to interact with the Delve Go debugger.

Description

This project implements a Model Context Protocol (MCP) server that integrates with the Delve Go debugger to enable AI assistants to debug Go applications. The server exposes a set of tools that allow LLMs to start, control, and interact with debug sessions.

You can find a working example at EXAMPLE.md.

Features

• Start debug sessions for Go programs
• Set breakpoints in code
• Step through code (next, step in, step out)
• Evaluate expressions in the context of a debug session
• Inspect variables and stack traces
• Manage multiple debug sessions

Installation

Prerequisites

• Go 1.21 or higher
• Delve debugger installed (go install github.com/go-delve/delve/cmd/dlv@latest)

Install

go install github.com/xhd2015/dlv-mcp/cmd/dlv-mcp@latest

Usage

Start the MCP server:

dlv-mcp --listen :9097

Then configure MCP Server at http://localhost:9097/sse, in Cursor or any MCP client.

Inspect the MCP Server

bunx @modelcontextprotocol/inspector dlv-mcp

Available Tools

Debug Session Management

• start_debug: Start a new debug session

  • program: Path to Go program to debug
  • args: Command line arguments for the program (optional)
  • mode: Debug mode (debug, test, or exec, default: debug)

• terminate_debug: Terminate a debug session

  • session_id: ID of the debug session to terminate

• list_debug_sessions: List active debug sessions

Breakpoint Management

• set_breakpoint: Set a breakpoint in a debug session
  • session_id: ID of the debug session
  • file: Source file to set breakpoint in (absolute path)
  • line: Line number to set breakpoint at

Execution Control

• continue: Continue execution in a debug session

  • session_id: ID of the debug session

• next: Step over current line in a debug session

  • session_id: ID of the debug session

• step_in: Step into function in a debug session

  • session_id: ID of the debug session

• step_out: Step out of function in a debug session

  • session_id: ID of the debug session

Inspection

• evaluate: Evaluate an expression in a debug session
  • session_id: ID of the debug session
  • expression: Expression to evaluate
  • frame_id: Stack frame ID (optional, default: 0)

Example Workflow

1. Start a debug session:

   start_debug program=/path/to/program.go
   

2. Set a breakpoint:

   set_breakpoint session_id=session-123456 file=/path/to/program.go line=15
   

3. Continue to breakpoint:

   continue session_id=session-123456
   

4. Evaluate an expression:

   evaluate session_id=session-123456 expression="myVariable"
   

5. Step over a line:

   next session_id=session-123456
   

6. Terminate the session:

   terminate_debug session_id=session-123456
   

Architecture

The server is built using the following components:

• MCP Server Layer: Implements the Model Context Protocol using mark3labs/mcp-go
• DAP Client Layer: Communicates with Delve’s DAP server
• Session Management: Maintains and manages debug sessions

Inspect The MCP Server

bunx @modelcontextprotocol/inspector go run ./cmd/dlv-mcp

Using the Demo Client

We’ve created a demo client that shows how to use the debugger-mcp server programmatically. The demo:

1. Starts the MCP server
2. Launches a debug session for ./testdata/hello.go
3. Tries to set a breakpoint and execute debugging commands
4. Properly terminates the session and server

To run the demo:

go run ./demo/main.go

The demo client showcases how to:

• Start and communicate with the MCP server using JSON-RPC
• Send tool calls using the correct format
• Parse and handle responses
• Deal with errors gracefully

Check out demo/main.go and demo/README.md for more details on the implementation.

License

MIT License