Claude Code MCP server mcp-cpp-server broken after Claude Code 2.1.28+ update

Hey everyone,

If you use **mcp-cpp-server** (the Rust-based MCP server for C++ code analysis via clangd) with **Claude Code**, it silently breaks after updating Claude Code to 2.1.28+.

`claude mcp list` shows the server as "Failed to connect" with no useful error. After digging through stderr logs, the actual error is:

```

Incompatible protocol version: client: 2025-11-25 server: 2025-06-18

```

**What happened:** Claude Code 2.1.28 switched to MCP protocol version `2025-11-25`, but `mcp-cpp-server` v0.2.2 uses `rust-mcp-sdk` 0.7.4 which only speaks protocol `2025-06-18`. The server starts fine but Claude rejects the handshake.

**The fix:** Upgrade `rust-mcp-sdk` from 0.7 to 0.8 in Cargo.toml, plus a few API changes the new SDK requires:

\- `Implementation` struct needs new fields (`description`, `icons`, `website_url`)

\- `create_server()` now takes a `McpServerOptions` struct instead of positional args

\- `handle_list_tools_request` / `handle_call_tool_request` signatures changed

\- Handler conversion uses `.to_mcp_server_handler()` now

I've submitted **PR #12** upstream: https://github.com/mpsm/mcp-cpp/pull/12

**To use it now** (before the PR merges):

```bash

git clone https://github.com/ninokth/mcp-cpp.git

cd mcp-cpp

git checkout fix/sdk-0.8-upgrade

cargo build --release

cp target/release/mcp-cpp-server \~/.cargo/bin/

```

After that, `claude mcp list` should show `cpp: Connected` and all three tools (`search_symbols`, `analyze_symbol_context`, `get_project_details`) work again.

Hope this helps anyone else who hit this wall.

https://redd.it/1qwg9zy
@r_cpp