Thanks so much to /u/thelastlokean for raving about this.
I've been spending days writing my own custom scripts with grep, ast-grep, and writing tracing through instrumentation hooks and open telemetry to get Claude to understand the structure of the various api calls and function calls.... Wow. Then Serena MCP (+ Claude Code) seems to be built exactly to solve that.

Within a few moments of reading some of the docs and trying it out I can immediately see this is a game changer.

Don't take my word, try it out. Especially if your project is starting to become more complex.

https://github.com/oraios/serena

I made a VS Code extension that acts as an MCP server, allowing Claude desktop (and other clients) to code in an active VS Code workspace. This was driven by my own needs; github copilot is somewhat restrictive with the number of requests every month on the Pro tier and plus I want Claude for non-coding tasks anyway. I have been using Serena, which works great, but it was a bit cumbersome for my workflow. (Not criticising Serena; it is very cool and I recommend checking it out! It's just a bit cumbersome to have to edit the configuration file every time I start a new project, since I have to juggle a large number of separate codebases for work. That is probably not the case for everyone, or even most people.)

This extension is inspired by Serena but is less fully featured in some ways. What it does do, however, is expose your active VS Code workspace, so that you can switch projects just by switching to a different folder/workspace configuration in VS Code. In addition, VS Code diagnostics (ie. the "problems" tab that shows syntax errors, linter warnings, etc.) are exposed as an MCP tool.

Let me know what you think! I have been coding for quite a while, but mostly in the high performance computing and scientific ML spaces, so Typescript is quite new to me and I did lean on Claude more than usual. If you want to contribute, PRs are greatly appreciated :)

Github: https://github.com/juehang/vscode-mcp-server
VS Code Marketplace: https://marketplace.visualstudio.com/items?itemName=JuehangQin.vscode-mcp-server

Here's a demo video:

Hi all,
I've been using the serena MCP with claude code inside VSCode, but it breaks the IDE integration workflow that allows me to see a diff view of the code changes. Does anyone have a "compromise" setup that gets most of the benefits of Serena without losing the diff view? Would it work to just remove the editing tools like regex replace, or at that point does Serena become a waste? Thanks!

I've been trying to get the Serena MCP server (https://github.com/oraios/serena) working with Claude Code running in Ubuntu WSL2, but I'm hitting a persistent connection issue. The server launches successfully but Claude Code never actually connects to it.

Environment Details:

• OS: Windows 11 with WSL2 (Ubuntu 24)

• Claude Code: v2.0.20 (running in WSL terminal)

• Terminal: VS Code integrated terminal (working directory: /mnt/d/Documents/Game Design Documents/Lianji)

• Serena: Installed via uvx from snap: astral-uv 0.8.17

• Project: Unity/C# project on Windows filesystem mounted at /mnt/d/...

• uvx location: /snap/bin/uvx (snap package)

• Node version in WSL: v18.20.6

Configuration Files:

~/.claude/settings.json:

json

{
  "feedbackSurveyState": {
    "lastShownTime": 1754083318070
  },
  "$schema": "https://json.schemastore.org/claude-code-settings.json",
  "mcpServers": {
    "serena": {
      "command": "/home/althrretha/.claude/start-serena.sh",
      "args": []
    }
  }
}

~/.claude/start-serena.sh:

bash

#!/bin/bash
# Serena MCP Server Launcher for Claude Code (stdio mode)
exec /snap/bin/uvx --from git+https://github.com/oraios/serena serena start-mcp-server --context ide-assistant --project "/mnt/d/Documents/Game Design Documents/Lianji"
```
(File has Unix line endings, chmod +x applied)

**What I've tried:**

1. **Initial attempt:** Used Windows `uvx.exe` path (`/mnt/c/Users/.../uvx.exe`) with Windows-style paths - server couldn't find project due to path format mismatch between WSL and Windows

2. **WSL-native uvx:** Installed via `sudo snap install astral-uv --classic`, updated config to use `/snap/bin/uvx` with WSL paths - server starts successfully when run manually but Claude Code never connects

3. **Fixed line endings:** Initial wrapper script had CRLF line endings causing "required file not found" error - fixed with `sed -i 's/\r$//'`

4. **HTTP transport attempt:** Added `--transport streamable-http --port 9121` - same result (connection starts, never completes)

5. **Verified Ref MCP server works:** The built-in Ref server connects successfully via HTTP, confirming Claude Code's MCP system is functional

**Current behavior:**

From `~/.claude/debug/latest`:
```
[DEBUG] MCP server "serena": Starting connection with timeout of 30000ms
[DEBUG] Writing to temp file: /home/althrretha/.claude.json.tmp.XXXX.XXXXXXXXX

Then... nothing. No completion message, no error, just timeout after 30 seconds.

Manual execution works perfectly:

bash

$ /home/althrretha/.claude/start-serena.sh
INFO  2025-10-16 21:08:12,684 [MainThread] serena.agent:__init__:203 - Number of exposed tools: 19
INFO  2025-10-16 21:08:12,927 [MainThread] serena.cli:start_mcp_server:172 - Initializing Serena MCP server
INFO  [MainThread] serena.agent:setup_mcp_server:563 - MCP server lifetime setup complete

Serena logs confirm full initialization with language server running (C# LSP has expected MSBuild warnings in WSL but core tools are available).

Testing observations:

• When Serena runs manually, ps aux shows two processes: the uv tool wrapper and the Python serena process

• Server listens on stdio by default (no HTTP port opened unless explicitly configured)

• Claude Desktop (non-WSL Windows app) connects to Serena successfully with same project path using Windows-style paths

• Closing Claude Desktop before starting Claude Code session doesn't resolve the issue

Hypothesis: The stdio pipe communication between Claude Code (Node.js-based, running in WSL) and the spawned Serena process (Python via uvx) is failing to complete the MCP initialization handshake. The process launches but something in the inter-process communication breaks down, possibly related to:

• WSL's stdin/stdout handling with snap-confined applications

• File descriptor inheritance issues

• Buffering problems in the pipe communication

Questions:

1. Has anyone successfully run stdio-based MCP servers with Claude Code in WSL2?

2. Is there a known workaround for snap-installed tools communicating via stdio with Node.js processes in WSL?

3. Should I try installing uvx via a different method (pip install?) to avoid snap confinement?

4. Are there any Claude Code debug flags that would give more visibility into why the MCP connection times out?

The fact that Claude Code successfully connects to the HTTP-based Ref server but fails with stdio-based Serena suggests the issue is specifically with stdio transport in my WSL environment.

Any insights appreciated!

I wanted to share my recent experience with two different AI-assisted development setups for a massive Laravel 12 project and get your thoughts. The project involves a migration of the old Laravel 8 to a new, fresh version of Laravel 12 by preserving dual Architecture with Modern Upgrades.

The old app has a package that contains extensive business logic (18+ models, 11+ controllers, complex validation rules)

Migration Strategy:

- Fresh Laravel 12 installation
- Filament 3.3 installation  
- Basic package structure setup
- Replace appzcoder/laravel-admin with Filament resources
- UserResource, RoleResource, PermissionResource creation
- RolePermissionSeeder with language permissions
- Test user creation and authentication setup
- Update composer.json for Laravel 12 compatibility
- Replace deprecated packages with new ones
- Update model factories and middleware registration
- Fix Laravel 12 compatibility issues
- Create a compatibility layer between Filament Shield and existing permissions
- Update ApplicationPermission, AdminPermission, CheckRole middleware
- Integrate URL-based permission system with Filament
- Backup existing database
- Run Laravel 12 migrations on fresh database
- Create data migration commands for preserving existing data
- Migrate users, roles, workers, workplaces, and all HR data
- Create Filament pages linking to custom routes used by a custom-written Laravel extension
- Update custom Package for Laravel 12
- Update navigation to show both systems
- Comprehensive testing of all functionality
- Performance optimization and bug fixes

The Contenders:

1. Claude Desktop app + Serena MCP

2. Codex + Serena MCP

I was initially using the Claude Desktop app with the Serena MCP, and for a while, it was a solid combination. However, recently I've hit some major productivity roadblocks. Claude started to "overthink" tasks, introducing features I never asked for and generating unnecessary markdown files outlining the tasks I had already explained. It felt like I was spending more time cleaning up after it than it was saving me.

The Game Changer: Codex + Serena MCP

On a whim, I switched to using Codex with the same Serena MCP setup, and the difference has been night and day. Here’s what stood out:

Codex gets it done in one shot. I've been consistently impressed with how Codex handles tasks. I provide my instructions, and it delivers the code exactly as requested, in a single pass. There's no back and forth, no need to correct extraneous additions. It's direct, efficient, and respects the scope of the task.

No unnecessary overhead. With Codex, I haven't had to deal with any of the "creative additions" I was experiencing with Claude. It doesn't add extra logic, features, or documentation that wasn't explicitly requested. This has been a massive time-saver and has made the development process much smoother.

In my experience, for a large, complex project like this, the straightforward, no-nonsense approach of Codex has been far more effective. It feels like a tool that's designed to be a precise instrument for developers, rather than a creative partner that sometimes goes off-script.

Has anyone else had similar experiences when comparing these (or other) AI models on large-scale projects? I'm curious to know if my experience is unique or if others have found certain models to be better suited for specific types of development workflows.

TL;DR: For my complex Laravel project, Codex + Serena MCP has been significantly more efficient and direct than Claude + Serena MCP. Codex completes tasks in one go without adding unrequested features, which has been a major boost to my productivity.

I am using Serena MCP, but I don't notice that Claude Code works better with it. In fact, anytime it calls Serena's tool, CC slows to a grind. I have my project indexed. Is it just me, or are MCPs just hype and not value adds?

I'm constantly hitting context limits faster with serena than without it

And honestly, I can't even tell if its actually helping/is beneficial at all

Anyone have any thoughts/experiences they'd like the share to help me understand if it's ACTUALLY helpful or not?

Thansk

Claude 4, in particular Opus, is amazing for coding. It has only two main downsides: high cost and a relatively small context window.

Fortunately, there is a free, open-source (MIT licensed) solution to help with both: the Serena MCP server, a toolbox that uses language servers (and quite some code on top of them) to allow an LLM to perform symbolic operations, including edits, directly on your codebase. You may have seen my post on it a while ago, when we had just published the project. It turns a vanilla LLM into a capable coding agent, or improves existing coding agents if included into them

Now, a few weeks and 1k stars later, we are nearing a first stable version. I have started evaluating it, and I'm blown away by the results so far! When using it on its own in Claude Desktop, it turns Claude into a careful and token-frugal agent, capable of acting on enormous projects without running into token limits. As a complement to an existing agentic solution, like Claude Code or some other coding agent, Serena significantly reduced costs in all my experiments while keeping or increasing the quality of the output.

None of it is surprising, of course. If you give me an IDE, I will obviously be better and faster at coding than if I had to code in something like word and use pure file-reads and edits. Why shouldn't the same hold for an LLM?

A quantitative evaluation on SWE-verified is on its way, but to just give a taste of what Serena can do, I created one PR on a benchmark task from sympy, with Opus running on Claude Desktop. It demonstrates how Opus intelligently uses the tools to explore, read and edit the codebase in the most token-efficient manner possible. For complete transparency, the onboarding conversation and the solution conversation are included. The same holds for Sonnet, but for Opus it's particularly useful, since due to its high cost, token efficiency becomes key.

Since Claude Code is now included into the pro subscription, the file-read based MCPs are largely obsolete for coding purposes (for example, the codemcp dev said he now stops the project). Not so for Serena, since the symbolic tools it offers give a valuable addition to Claude Code, rather than being replaced by it.

Even though sympy is a huge repository, the Opus+Serena combo went through it like a breeze. For anyone wanting to have cheaper and faster coding agents, especially on larger projects, I highly recommend looking into Serena! We are still early in the journey, but I think the promise is very high.