https://github.com/JDevlieghere created https://github.com/llvm/llvm-project/pull/145935
Document how to use MCP support in LLDB. I expect this to change significantly as the feature matures. For now it covers configuring the server and two example clients. >From 2b6a7e22481761b244e98dff00f905cf32a7d696 Mon Sep 17 00:00:00 2001 From: Jonas Devlieghere <jo...@devlieghere.com> Date: Thu, 26 Jun 2025 10:31:09 -0700 Subject: [PATCH] [lldb] Document MCP support in LLDB --- lldb/docs/index.rst | 1 + lldb/docs/use/mcp.md | 68 ++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 69 insertions(+) create mode 100644 lldb/docs/use/mcp.md diff --git a/lldb/docs/index.rst b/lldb/docs/index.rst index 1ffdb08a1ca2c..d49d0d8d5a733 100644 --- a/lldb/docs/index.rst +++ b/lldb/docs/index.rst @@ -135,6 +135,7 @@ interesting areas to contribute to lldb. use/ondemand use/aarch64-linux use/symbolfilejson + use/mcp use/troubleshooting use/links Man Page <man/lldb> diff --git a/lldb/docs/use/mcp.md b/lldb/docs/use/mcp.md new file mode 100644 index 0000000000000..a89740545e5f4 --- /dev/null +++ b/lldb/docs/use/mcp.md @@ -0,0 +1,68 @@ +# Model Context Protocol (MCP) + +LLDB supports for the [Model Context Protocol][1] (MCP). This structured, +machine-friendly protocol allows AI models to access and interact with external +tools, such as the debugger. Using MCP, an AI agent can execute LLDB commands +to control the debugger: set breakpoints, inspect memory, step through code. +This can range from helping you run a specific command you can't immediately +remember to a fully agent-driven debugging experiences + +## MCP Server + +To start the MCP server in LLDB, use the `protocol-server start` command. +Specify `MCP` as the protocol and provide a URI to listen on. For example, to +start listening for local TCP connections on port `59999`, use the following +command: + +``` +(lldb) protocol-server start MCP listen://localhost:59999 +MCP server started with connection listeners: connection://[::1]:59999, connection://[127.0.0.1]:59999 +``` + +The server will automatically stop when exiting LLDB, or it can be stopped +explicitly with the `protocol-server stop` command. + +``` +(lldb) protocol-server stop MCP +``` + +## MCP Client + +MCP uses standard input/output (stdio) for communication between client and +server. The exact configuration depends on the client, but most applications +allow you to specify an MCP server as a binary and arguments. This means that +you need to use something like `netcat` to connect to LLDB's MCP server and +forward communication over stdio over the network connection. + +Configuration example for [Claude Code][2]: + +``` +{ + "mcpServers": { + "tool": { + "command": "/usr/bin/nc", + "args": ["localhost", "59999"] + } + } +} +``` + +Configuration example for [Visual Studio Code][3]: + +``` +{ + "mcp": { + "servers": { + "lldb": { + "type": "stdio", + "command": "/usr/bin/nc", + "args": ["localhost", "59999"] + } + } + } +} +``` + +[1]: https://modelcontextprotocol.io +[2]: https://modelcontextprotocol.io/quickstart/user +[3]: https://code.visualstudio.com/docs/copilot/chat/mcp-servers _______________________________________________ lldb-commits mailing list lldb-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits