BUG: MCP servers fail to connect in Claude Code despite correct configuration

was this fixed? i'm still having issues with claude code connecting to supabase mcp

Same issue for basically any mcp server

Experiencing the same issue.
Restarting Claude several times and eventually it connects. But it's almost like the MCP server needs to be 'warmed up'?

A restart of claude, initiazes the app but page is blank. Go to settings, then closing settings, and then the page populates.

macOS: Sequoia 15.5
node version v22.16.0

UPDATE: Ok, folks. So some complexity here.

1. I had Node installed but npm was installed globally so npm --version would returned a 'not recognized'.
2. I did not have the location of npm.
3. Re-installed npm (kinda) and added the path to my ~.zshrc

I'm still testing, but so far seems like it's working much faster and bettah.

In short;

1. Make sure npm is running locally.
2. Make sure ~.zshrc has the 'export NVM_DIR="$HOME/ .nvm" in the config.
3. Shut down iTerm, shut-down Claude Desktop. and fire everything back up. Should work.

I have the same issue .I just had the demo server code in demo server python sdk . It also give me cant connect to the mcp server. Any suggestions?

Can you try running claude --debug to see if anything is displayed?

i tried to but i cant get to run claude debug .cli is not found and I dont think its the issue since im using python sdk.

Having the same problem with a couple of MCP servers.

wasted hours trying to get gitea MCP working with claude-code

I'm also seeing this. The MCP server works fine in Claude Desktop but Claude Code can't find any tools for it

Having the same issue - It will work fine for a few tool uses, and then spontaneously disconnect and can't reconnect with restarting claude code, sometimes a few times. MacOS.

This is still an issue and a very breaking issue. It should be prioritized

Hey all, I'm trying to understand all of the reports here. Is this a single issue or are there multiple things going on here?

@timjrobinson can you share more about the server config you're using? Does the server show as connected in /mcp but says it has no tools when you drill into the details?

@seanmozeik are you using stdio servers or remote servers? Or is this for any server?

If anyone is able to run with claude --debug and share output from that, that'll really help. You can also find MCP logs in ~/Library/Caches/claude-cli-nodejs/ (within different subdirectories there).

Mine just timeout after the limit is reached . The Servers work fine on Claude Desktop. I import them over to claude code using claude mcp add-from-claude-desktop command.

Sometimes the servers work in Claude Code, other times more often than not they just dont work. Very buggy

[DEBUG] MCP server "mcp-server-firecrawl": Connection failed: Error: Connection to MCP server "mcp-server-firecrawl" timed out after 30000ms
[DEBUG] MCP server "mcp-server-firecrawl": Error message: Connection to MCP server "mcp-server-firecrawl" timed out after 30000ms
[DEBUG] MCP server "mcp-server-firecrawl": Error stack: Error: Connection to MCP server "mcp-server-firecrawl" timed out after 30000ms
at Timeout._onTimeout (file:///home/username/.nvm/versions/node/v22.16.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:1383:5751)
at listOnTimeout (node:internal/timers:588:17)
at process.processTimers (node:internal/timers:523:7)
╭────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
[DEBUG] MCP server "firebase-mcp": Connection failed: Error: Connection to MCP server "firebase-mcp" timed out after 30000ms
[DEBUG] MCP server "firebase-mcp": Error message: Connection to MCP server "firebase-mcp" timed out after 30000ms
[DEBUG] MCP server "firebase-mcp": Error stack: Error: Connection to MCP server "firebase-mcp" timed out after 30000ms
at Timeout._onTimeout (file:///home/username/.nvm/versions/node/v22.16.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:1383:5751)
at listOnTimeout (node:internal/timers:588:17)
at process.processTimers (node:internal/timers:523:7)
╭────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
[DEBUG] MCP server "playwright": Connection failed: Error: Connection to MCP server "playwright" timed out after 30000ms
[DEBUG] MCP server "playwright": Error message: Connection to MCP server "playwright" timed out after 30000ms
[DEBUG] MCP server "playwright": Error stack: Error: Connection to MCP server "playwright" timed out after 30000ms
at Timeout._onTimeout (file:///home/username/.nvm/versions/node/v22.16.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:1383:5751)
at listOnTimeout (node:internal/timers:588:17)
at process.processTimers (node:internal/timers:523:7)
╭────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
[DEBUG] MCP server "youtube-transcript": Connection failed: Error: Connection to MCP server "youtube-transcript" timed out after 30000ms
[DEBUG] MCP server "youtube-transcript": Error message: Connection to MCP server "youtube-transcript" timed out after 30000ms
[DEBUG] MCP server "youtube-transcript": Error stack: Error: Connection to MCP server "youtube-transcript" timed out after 30000ms
at Timeout._onTimeout (file:///home/username/.nvm/versions/node/v22.16.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:1383:5751)
at listOnTimeout (node:internal/timers:588:17)
at process.processTimers (node:internal/timers:523:7)
╭────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
[DEBUG] MCP server "ElevenLabs": Connection failed: Error: Connection to MCP server "ElevenLabs" timed out after 30000ms
[DEBUG] MCP server "ElevenLabs": Error message: Connection to MCP server "ElevenLabs" timed out after 30000ms
[DEBUG] MCP server "ElevenLabs": Error stack: Error: Connection to MCP server "ElevenLabs" timed out after 30000ms
at Timeout._onTimeout (file:///home/username/.nvm/versions/node/v22.16.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:1383:5751)
at listOnTimeout (node:internal/timers:588:17)
at process.processTimers (node:internal/timers:523:7)
╭────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮[DEBUG] MCP server "qdrant": Connection failed: Error: Connection to MCP server "qdrant" timed out after 30000ms
[DEBUG] MCP server "qdrant": Error message: Connection to MCP server "qdrant" timed out after 30000ms
[DEBUG] MCP server "qdrant": Error stack: Error: Connection to MCP server "qdrant" timed out after 30000ms
at Timeout._onTimeout (file:///home/username/.nvm/versions/node/v22.16.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:1383:5751)
at listOnTimeout (node:internal/timers:588:17)
at process.processTimers (node:internal/timers:523:7)
╭────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
[DEBUG] MCP server "postgres": Connection failed: Error: Connection to MCP server "postgres" timed out after 30000ms
[DEBUG] MCP server "postgres": Error message: Connection to MCP server "postgres" timed out after 30000ms
[DEBUG] MCP server "postgres": Error stack: Error: Connection to MCP server "postgres" timed out after 30000ms
at Timeout._onTimeout (file:///home/username/.nvm/versions/node/v22.16.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:1383:5751)
at listOnTimeout (node:internal/timers:588:17)
at process.processTimers (node:internal/timers:523:7)

@ashwin-ant the MCP server has started working for me again after adding it in Claude code explicitly with claude mcp add it can see the tools. Previously when using the claude file from claude desktop it wasn't working (I guess code and desktop use different configs and I didn't realize?)

Can confirm I also have this issue with FastMCP stdio transport. I've been trying this for a while, I've wrapped calls and a lot more, but for whatever reason it really struggles.

[ERROR] MCP server "claude-mcp-orchestration" Server stderr: {"event": "    + Exception Group Traceback (most recent call last):", "timestamp": "2025-07-07T01:26:24.151820Z"}
[ERROR] MCP server "claude-mcp-orchestration" Server stderr: {"event": "    |   File \"/home/zach/.local/share/uv/tools/claude-mcp-tools/lib/python3.13/site-packages/claude_mcp_tools/orchestration_server.py\", line 1918, in main", "timestamp": "2025-07-07T01:26:24.151866Z"}
{"event": "    |     app.run()", "timestamp": "2025-07-07T01:26:24.151888Z"}
{"event": "    |     ~~~~~~~^^", "timestamp": "2025-07-07T01:26:24.151901Z"}
{"event": "    |   File \"/home/zach/.local/share/uv/tools/claude-mcp-tools/lib/python3.13/site-packages/fastmcp/server/server.py\", line 328, in run", "timestamp": "2025-07-07T01:26:24.151913Z"}
{"event": "    |     anyio.run(", "timestamp": "2025-07-07T01:26:24.151922Z"}
{"event": "    |     ~~~~~~~~~^", "timestamp": "2025-07-07T01:26:24.151929Z"}
{"event": "    |         partial(", "timestamp": "2025-07-07T01:26:24.151937Z"}
{"event": "    |         ^^^^^^^^", "timestamp": "2025-07-07T01:26:24.151945Z"}
{"event": "    |     ...<4 lines>...", "timestamp": "2025-07-07T01:26:24.151952Z"}
{"event": "    |         )", "timestamp": "2025-07-07T01:26:24.151960Z"}
{"event": "    |         ^", "timestamp": "2025-07-07T01:26:24.151967Z"}
{"event": "    |     )", "timestamp": "2025-07-07T01:26:24.151974Z"}
{"event": "    |     ^", "timestamp": "2025-07-07T01:26:24.151982Z"}
{"event": "    |   File \"/home/zach/.local/share/uv/tools/claude-mcp-tools/lib/python3.13/site-packages/anyio/_core/_eventloop.py\", line 74, in run", "timestamp": "2025-07-07T01:26:24.151989Z"}
{"event": "    |     return async_backend.run(func, args, {}, backend_options)", "timestamp": "2025-07-07T01:26:24.151997Z"}
{"event": "    |            ~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^", "timestamp": "2025-07-07T01:26:24.152004Z"}
{"event": "    |   File \"/home/zach/.local/share/uv/tools/claude-mcp-tools/lib/python3.13/site-packages/anyio/_backends/_asyncio.py\", line 2310, in run", "timestamp": "2025-07-07T01:26:24.152011Z"}
{"event": "    |     return runner.run(wrapper())", "timestamp": "2025-07-07T01:26:24.152019Z"}
{"event": "    |            ~~~~~~~~~~^^^^^^^^^^^", "timestamp": "2025-07-07T01:26:24.152026Z"}
{"event": "    |   File \"/home/zach/.local/share/uv/python/cpython-3.13.1-linux-x86_64-gnu/lib/python3.13/asyncio/runners.py\", line 118, in run", "timestamp": "2025-07-07T01:26:24.152033Z"}
{"event": "    |     return self._loop.run_until_complete(task)", "timestamp": "2025-07-07T01:26:24.152041Z"}
{"event": "    |            ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^", "timestamp": "2025-07-07T01:26:24.152048Z"}
{"event": "    |   File \"uvloop/loop.pyx\", line 1518, in uvloop.loop.Loop.run_until_complete", "timestamp": "2025-07-07T01:26:24.152055Z"}
{"event": "    |   File \"/home/zach/.local/share/uv/tools/claude-mcp-tools/lib/python3.13/site-packages/anyio/_backends/_asyncio.py\", line 2298, in wrapper", "timestamp": "2025-07-07T01:26:24.152063Z"}
{"event": "    |     return await func(*args)", "timestamp": "2025-07-07T01:26:24.152070Z"}
{"event": "    |            ^^^^^^^^^^^^^^^^^", "timestamp": "2025-07-07T01:26:24.152077Z"}
{"event": "    |   File \"/home/zach/.local/share/uv/tools/claude-mcp-tools/lib/python3.13/site-packages/fastmcp/server/server.py\", line 303, in run_async", "timestamp": "2025-07-07T01:26:24.152085Z"}
{"event": "    |     await self.run_stdio_async(", "timestamp": "2025-07-07T01:26:24.152092Z"}
{"event": "    |     ...<2 lines>...", "timestamp": "2025-07-07T01:26:24.152099Z"}
{"event": "    |     )", "timestamp": "2025-07-07T01:26:24.152108Z"}
{"event": "    |   File \"/home/zach/.local/share/uv/tools/claude-mcp-tools/lib/python3.13/site-packages/fastmcp/server/server.py\", line 1351, in run_stdio_async", "timestamp": "2025-07-07T01:26:24.152116Z"}
{"event": "    |     async with stdio_server() as (read_stream, write_stream):", "timestamp": "2025-07-07T01:26:24.152126Z"}
{"event": "    |                ~~~~~~~~~~~~^^", "timestamp": "2025-07-07T01:26:24.152136Z"}
{"event": "    |   File \"/home/zach/.local/share/uv/python/cpython-3.13.1-linux-x86_64-gnu/lib/python3.13/contextlib.py\", line 235, in __aexit__", "timestamp": "2025-07-07T01:26:24.152146Z"}
{"event": "    |     await self.gen.athrow(value)", "timestamp": "2025-07-07T01:26:24.152155Z"}
{"event": "    |   File \"/home/zach/.local/share/uv/tools/claude-mcp-tools/lib/python3.13/site-packages/mcp/server/stdio.py\", line 85, in stdio_server", "timestamp": "2025-07-07T01:26:24.152165Z"}
{"event": "    |     async with anyio.create_task_group() as tg:", "timestamp": "2025-07-07T01:26:24.152201Z"}
{"event": "    |                ~~~~~~~~~~~~~~~~~~~~~~~^^", "timestamp": "2025-07-07T01:26:24.152213Z"}
{"event": "    |   File \"/home/zach/.local/share/uv/tools/claude-mcp-tools/lib/python3.13/site-packages/anyio/_backends/_asyncio.py\", line 772, in __aexit__", "timestamp": "2025-07-07T01:26:24.152223Z"}
{"event": "    |     raise BaseExceptionGroup(", "timestamp": "2025-07-07T01:26:24.152232Z"}
{"event": "    |         \"unhandled errors in a TaskGroup\", self._exceptions", "timestamp": "2025-07-07T01:26:24.152239Z"}
{"event": "    |     ) from None", "timestamp": "2025-07-07T01:26:24.152247Z"}
{"event": "    | ExceptionGroup: unhandled errors in a TaskGroup (1 sub-exception)", "timestamp": "2025-07-07T01:26:24.152256Z"}
{"event": "    +-+---------------- 1 ----------------", "timestamp": "2025-07-07T01:26:24.152263Z"}
{"event": "      | Exception Group Traceback (most recent call last):", "timestamp": "2025-07-07T01:26:24.152271Z"}
{"event": "      |   File \"/home/zach/.local/share/uv/tools/claude-mcp-tools/lib/python3.13/site-packages/mcp/server/stdio.py\", line 88, in stdio_server", "timestamp": "2025-07-07T01:26:24.152279Z"}
{"event": "      |     yield read_stream, write_stream", "timestamp": "2025-07-07T01:26:24.152287Z"}
{"event": "      |   File \"/home/zach/.local/share/uv/tools/claude-mcp-tools/lib/python3.13/site-packages/fastmcp/server/server.py\", line 1353, in run_stdio_async", "timestamp": "2025-07-07T01:26:24.152295Z"}
{"event": "      |     await self._mcp_server.run(", "timestamp": "2025-07-07T01:26:24.152303Z"}
{"event": "      |     ...<5 lines>...", "timestamp": "2025-07-07T01:26:24.152311Z"}
{"event": "      |     )", "timestamp": "2025-07-07T01:26:24.152318Z"}
{"event": "      |   File \"/home/zach/.local/share/uv/tools/claude-mcp-tools/lib/python3.13/site-packages/mcp/server/lowlevel/server.py\", line 569, in run", "timestamp": "2025-07-07T01:26:24.152326Z"}
{"event": "      |     async with AsyncExitStack() as stack:", "timestamp": "2025-07-07T01:26:24.152334Z"}
{"event": "      |                ~~~~~~~~~~~~~~^^", "timestamp": "2025-07-07T01:26:24.152341Z"}
{"event": "      |   File \"/home/zach/.local/share/uv/python/cpython-3.13.1-linux-x86_64-gnu/lib/python3.13/contextlib.py\", line 768, in __aexit__", "timestamp": "2025-07-07T01:26:24.152362Z"}
{"event": "      |     raise exc", "timestamp": "2025-07-07T01:26:24.152380Z"}
{"event": "      |   File \"/home/zach/.local/share/uv/python/cpython-3.13.1-linux-x86_64-gnu/lib/python3.13/contextlib.py\", line 751, in __aexit__", "timestamp": "2025-07-07T01:26:24.152391Z"}
{"event": "      |     cb_suppress = await cb(*exc_details)", "timestamp": "2025-07-07T01:26:24.152401Z"}
{"event": "      |                   ^^^^^^^^^^^^^^^^^^^^^^", "timestamp": "2025-07-07T01:26:24.152411Z"}
{"event": "      |   File \"/home/zach/.local/share/uv/tools/claude-mcp-tools/lib/python3.13/site-packages/mcp/shared/session.py\", line 218, in __aexit__", "timestamp": "2025-07-07T01:26:24.152420Z"}
{"event": "      |     return await self._task_group.__aexit__(exc_type, exc_val, exc_tb)", "timestamp": "2025-07-07T01:26:24.152428Z"}
{"event": "      |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^", "timestamp": "2025-07-07T01:26:24.152436Z"}
{"event": "      |   File \"/home/zach/.local/share/uv/tools/claude-mcp-tools/lib/python3.13/site-packages/anyio/_backends/_asyncio.py\", line 772, in __aexit__", "timestamp": "2025-07-07T01:26:24.152444Z"}
{"event": "      |     raise BaseExceptionGroup(", "timestamp": "2025-07-07T01:26:24.152451Z"}
{"event": "      |         \"unhandled errors in a TaskGroup\", self._exceptions", "timestamp": "2025-07-07T01:26:24.152459Z"}
{"event": "      |     ) from None", "timestamp": "2025-07-07T01:26:24.152467Z"}
{"event": "      | ExceptionGroup: unhandled errors in a TaskGroup (1 sub-exception)", "timestamp": "2025-07-07T01:26:24.152475Z"}
{"event": "      +-+---------------- 1 ----------------", "timestamp": "2025-07-07T01:26:24.152483Z"}
{"event": "        | Exception Group Traceback (most recent call last):", "timestamp": "2025-07-07T01:26:24.152490Z"}
[ERROR] MCP server "claude-mcp-orchestration" Server stderr: {"event": "        |   File \"/home/zach/.local/share/uv/tools/claude-mcp-tools/lib/python3.13/site-packages/mcp/server/lowlevel/server.py\", line 580, in run", "timestamp": "2025-07-07T01:26:24.152498Z"}
{"event": "        |     async with anyio.create_task_group() as tg:", "timestamp": "2025-07-07T01:26:24.152506Z"}
{"event": "        |                ~~~~~~~~~~~~~~~~~~~~~~~^^", "timestamp": "2025-07-07T01:26:24.152514Z"}
{"event": "        |   File \"/home/zach/.local/share/uv/tools/claude-mcp-tools/lib/python3.13/site-packages/anyio/_backends/_asyncio.py\", line 772, in __aexit__", "timestamp": "2025-07-07T01:26:24.152521Z"}
{"event": "        |     raise BaseExceptionGroup(", "timestamp": "2025-07-07T01:26:24.152529Z"}
{"event": "        |         \"unhandled errors in a TaskGroup\", self._exceptions", "timestamp": "2025-07-07T01:26:24.152536Z"}
{"event": "        |     ) from None", "timestamp": "2025-07-07T01:26:24.152544Z"}
{"event": "        | ExceptionGroup: unhandled errors in a TaskGroup (1 sub-exception)", "timestamp": "2025-07-07T01:26:24.152551Z"}
{"event": "        +-+---------------- 1 ----------------", "timestamp": "2025-07-07T01:26:24.152558Z"}
{"event": "          | Traceback (most recent call last):", "timestamp": "2025-07-07T01:26:24.152566Z"}
{"event": "          |   File \"/home/zach/.local/share/uv/tools/claude-mcp-tools/lib/python3.13/site-packages/mcp/server/lowlevel/server.py\", line 604, in _handle_message", "timestamp": "2025-07-07T01:26:24.152573Z"}
{"event": "          |     await self._handle_request(message, req, session, lifespan_context, raise_exceptions)", "timestamp": "2025-07-07T01:26:24.152581Z"}
{"event": "          |   File \"/home/zach/.local/share/uv/tools/claude-mcp-tools/lib/python3.13/site-packages/mcp/server/lowlevel/server.py\", line 653, in _handle_request", "timestamp": "2025-07-07T01:26:24.152589Z"}
{"event": "          |     await message.respond(response)", "timestamp": "2025-07-07T01:26:24.152596Z"}
{"event": "          |   File \"/home/zach/.local/share/uv/tools/claude-mcp-tools/lib/python3.13/site-packages/mcp/shared/session.py\", line 131, in respond", "timestamp": "2025-07-07T01:26:24.152603Z"}
{"event": "          |     await self._session._send_response(  # type: ignore[reportPrivateUsage]", "timestamp": "2025-07-07T01:26:24.152611Z"}
{"event": "          |         request_id=self.request_id, response=response", "timestamp": "2025-07-07T01:26:24.152618Z"}
{"event": "          |     )", "timestamp": "2025-07-07T01:26:24.152626Z"}
{"event": "          |   File \"/home/zach/.local/share/uv/tools/claude-mcp-tools/lib/python3.13/site-packages/mcp/shared/session.py\", line 329, in _send_response", "timestamp": "2025-07-07T01:26:24.152633Z"}
{"event": "          |     await self._write_stream.send(session_message)", "timestamp": "2025-07-07T01:26:24.152640Z"}
{"event": "          |   File \"/home/zach/.local/share/uv/tools/claude-mcp-tools/lib/python3.13/site-packages/anyio/streams/memory.py\", line 242, in send", "timestamp": "2025-07-07T01:26:24.152648Z"}
{"event": "          |     self.send_nowait(item)", "timestamp": "2025-07-07T01:26:24.152655Z"}
{"event": "          |     ~~~~~~~~~~~~~~~~^^^^^^", "timestamp": "2025-07-07T01:26:24.152663Z"}
{"event": "          |   File \"/home/zach/.local/share/uv/tools/claude-mcp-tools/lib/python3.13/site-packages/anyio/streams/memory.py\", line 211, in send_nowait", "timestamp": "2025-07-07T01:26:24.152670Z"}
{"event": "          |     raise ClosedResourceError", "timestamp": "2025-07-07T01:26:24.15

this is Python FastMCP, but it is consistently happening in my package with Claude Code, and then the entire MCP server crashes after, which is the real issue, because then I can't use it. Not sure if it's directly connected, but I would love to contribute to a fix

I'm running claude code on wsl and claude seems to intermitently detect or fail to detect by project scoped mcp's in .mcp.json. This is a pain as i want to keep my MCP config project scoped and stored with the project in github

The filesystem mcp, probably one of the most widely used ones still refuses to connect.. I love Claude Code but this breaking constantly is very annoying.

did update to. v1.0.44, and all my 11 mcps stopped working instantly, even the custom ones, also claude code started crashing on "escape" but i can see there are other issues mentioning this

I have the same issue, running in WSL with MCPs for Supabase and Context7 on a NextJS project. Gemini CLI works fine and Claude code works fine in other projects.

Im sorry but this MCP thing needs to be sorted out. The MCP concept is great but I've rarely seen a tech so poorly handled, this is on par with javascript libraries in the 10s. MCP is a mess. It is unreliable, every vendor has a different implementation. Its frankly too annoying, and Anthropic has the least excuses to be getting this wrong still.

Not only do they make it ridiculously annoying on Claude Code and Claude Desktop but its not rock solid. CLine and Roo have MCP marketplace, one click and install. ANd its mostly working fine. I need CC and CD, but I also need reliable and easy MCP.

For the love of god, stop making new features and make the basics work reliably please.

I hope Claude isn’t writing the MCP code 😢
Shoddy work. Very very expensive.
No motivation to cache parses which burn up all my tokens.

Also experiencing this issue with MCPs not available in Claude code. Any updates on a fix here?

I'm on v1.0.44 - I've just moved the scope of my MCP's from project to user and that has worked - not ideal, but at least they work

We're investigating a potential fix. Some questions:

• Is this strictly happening to people with multiple MCP servers? How many do you have?
• Are the servers configured as npx commands or as local node/docker commands? Or a mix? It sounds like it's both, but want to make sure.

We're investigating a potential fix. Some questions: Is this strictly happening to people with multiple MCP servers? How many do you have? Are the servers configured as npx commands or as local node/docker commands? Or a mix? It sounds like it's both, but want to make sure.

Multiple MCP servers some at users level, some at project level in .mcp.json configured with NPX commands. @AndyDavo suggestion worked for me

We're investigating a potential fix. Some questions: Is this strictly happening to people with multiple MCP servers? How many do you have? Are the servers configured as npx commands or as local node/docker commands? Or a mix? It sounds like it's both, but want to make sure.

I just installed Claude Code today; also getting the mcp failure to connect. I had these two:

"xcode-build": {
  "command": "npx",
  "args": [
    "-y",
    "@cameroncooke/xcode-build-mcp"
  ],
  "env": {}
},
"apple-doc-mcp": {
  "type": "stdio",
  "command": "/Users/ggonz/Developer/apple-doc-mcp",
  "args": [],
  "env": {}
}

It's still not working if I remove either one and try with just one.

I have the following;
Mostly it's working fine.

1. Occassionally when I fire up Claude I will have a blank Claude window.
2. if I click 'settings' in Claude, then close settings the page will load.
3. Occassionally one or more of the MCP servers don't fire up.
4. in the event #3 occurs, I shutdown Claude then it seems the MCP's fire up.

I have a;

1. filesystem mcp pointing to 3 directories.
2. puppeteer mcp
3. github mcp
4. obsidian mcp pointing to vault 1
5. another obsidian mcp pointing to vault 2

I also have all the bells and whistled turned on; IE

1. Extended Thinking
2. Web search
3. google drive search
4. gmail search
5. calendar search
6. Atlassian

Here is the error from the mcp-server log for one of my obsidian mcp's. I'm guessing a caching problem but not sure.
I'm also getting a message to upgrade npm but at this point I'm kinda afraid to.
Current version: 10.9.2

2025-07-10T14:58:42.412Z [mcp-obsidian-linnaean] [info] Server started and connected successfully { metadata: undefined }
2025-07-10T14:58:42.416Z [mcp-obsidian-linnaean] [info] Message from client: {"method":"initialize","params":{"protocolVersion":"2024-11-05","capabilities":{},"clientInfo":{"name":"claude-ai","version":"0.1.0"}},"jsonrpc":"2.0","id":0} { metadata: undefined }
npm error code ENOTEMPTY
npm error syscall rename
npm error path /Users/userName/.npm/_npx/0496d3f111c50e47/node_modules/@modelcontextprotocol/sdk
npm error dest /Users/userName/.npm/_npx/0496d3f111c50e47/node_modules/@modelcontextprotocol/.sdk-SXsa55pC
npm error errno -66
npm error ENOTEMPTY: directory not empty, rename '/Users/userName/.npm/_npx/0496d3f111c50e47/node_modules/@modelcontextprotocol/sdk' -> '/Users/userName/.npm/_npx/0496d3f111c50e47/node_modules/@modelcontextprotocol/.sdk-SXsa55pC'
npm error A complete log of this run can be found in: /Users/userName/.npm/_logs/2025-07-10T14_58_43_527Z-debug-0.log

did update to. v1.0.44, and all my 11 mcps stopped working instantly, even the custom ones, also claude code started crashing on "escape" but i can see there are other issues mentioning this

e're investigating a potential fix. Some questions: Is this strictly happening to people with multiple MCP servers? How many do you have? Are the servers configured as npx commands or as local node/docker commands? Or a mix? It sounds like it's both, but want to make sure.

Had to reinstall all MCPs after they crashed following a recent update. My ~/.claude.json also got corrupted (ballooned to 3MB+ from paste history).

Here's my current MCP setup after rebuilding everything:

🌍 Global User Level (~/Library/Application Support/Claude/claude_desktop_config.json):

• MCP_DOCKER: docker mcp gateway run - i've installed it after all MCPs crashed after update.

📁 Project Level (.mcp.json):

• devlog-core: node ./mcp-devlog/bin/devlog-core.js
• devlog-search: node ./mcp-devlog/bin/devlog-search.js
• devlog-analytics: node ./mcp-devlog/bin/devlog-analytics.js
• devlog-planning: node ./mcp-devlog/bin/devlog-planning.js
• chromadb-devlog: python3 ./mcp-servers/chromadb/server.py
• elevenlabs-mcp: npx elevenlabs-mcp

💻 Local/Session Level (.claude-code-mcp.json + claude mcp list):

• playwright-mcp: node ~/work/playwright-mcp/dist/index.js
• devlog-core: node ./mcp-devlog/bin/devlog-core.js
• devlog-search: node ./mcp-devlog/bin/devlog-search.js
• devlog-analytics: node ./mcp-devlog/bin/devlog-analytics.js
• devlog-planning: node ./mcp-devlog/bin/devlog-planning.js
• chromadb-devlog: python3 ~/project/mcp-servers/chromadb/server.py
• devlog-mcp: node ~/project/mcp-devlog/dist/cjs/server.js (custom MCP with ChromaDB integration)
• notion-mcp: node ~/project/mcp-servers/notion-custom/server.js
• think-mcp-server: ~/project/mcp-servers/think-mcp-server/start.sh
• telegram-notifier: node ~/project/mcp-servers/telegram/server-enhanced.js
• playwright: http://localhost:9002/mcp (HTTP)

📝 Additional Local Config (.claude-code-mcp.json):

• mcp-atlassian-sse: http://localhost:9000/sse
• nx-mcp: npx nx-mcp
• devlog: node mcp-devlog/dist/cjs/server.js - specific projects - specific stuff
• think-mcp: node mcp-servers/think-mcp-server/dist/server.js
• perplexity-researcher: [pending reinstall]
• perplexity-ask: [pending reinstall]

Note: devlog is my custom MCP with ChromaDB vector search included. Some MCPs are running through Docker containers.

When I use the same .mcp.json file in ubuntu claude code works fine. However, in WSL under Windows, Ubuntu prompts that it cannot be connected

We're investigating a potential fix. Some questions: Is this strictly happening to people with multiple MCP servers? How many do you have? Are the servers configured as npx commands or as local node/docker commands? Or a mix? It sounds like it's both, but want to make sure.

Just my local gitea server, which Gemini connected to immediately.
https://gitea.com/gitea/gitea-mcp

just
sudo chown -R 501:20 "$HOME/.npm"
or
Try executing the command in the mcp server settings and check the log.
ex) zsh) npx -y ios-simulator-mcp

Heads up to other devs using MCP servers with Claude Code:

Try running claude --verbose once and watch what happens at startup. You might be surprised.

I started investigating this after I almost hit all my token limits surprisingly quickly in a previous session. I discovered that ALL those MCP tool descriptions are being loaded into your context immediately, whether you use verbose mode or not. The verbose flag just makes it visible.

This means if you've been wondering why you're hitting token limits faster lately, this is probably why. Every session starts with potentially thousands of tokens already consumed by tool descriptions you might never use.

It's worth checking out with --verbose just to see the actual impact. Pretty eye-opening to see how much context is being eaten up before you even start coding.

Based on my research, MCP tool descriptions used to load on-demand (only when you actually use the tool), which seems like the intended behavior. This appears to be an unintended change in recent versions.

I'm currently optimizing my MCP setup to only keep the most essential tools enabled until this gets sorted out. The Claude Code team has built an amazing tool, and I'm sure they'll address this once they're aware of the impact.

Hope this helps others understand their token usage better!

I also have this issue. MCP servers work in VS Code and Cursor IDE, but Claude Code tells me it's not exposed to the tools and that it's a CC API issue.

After some tests, I see that claude totally ignores any MCP servers defined in the local project's .claude.json and .mcp.json. That is very easy to check, just create or edit that file, add some valid MCP server definition, and run "claude mcp list", it will not list whatever you added there.
Instead, it only reads ~/.claude.json, which has a list of MCP servers per each path it was used and each parent directory until the user's home directory.

Same issue, after hours trying, i’ve been UNABLE TO USE NOTION MCP from Claude CODE, despite that it’s 55% of the times functional on browser and claude DESKTOP.

Claude Code MCP is broken across ALL platforms?

Skip for the moment from using MCP in Claude Code entirely, regardless of OS?

2 days i cant setup any mcps inside claude code. The command in terminal "claude mcp list" shows that i have working mcps,but the command in CC "/mcp" shows 'No MCP servers configured'. I did everything and it always shows 'No MCP servers configured' error.

OS: Windows 10
Installation: npm-global (1.0.62)
Problem: "The interactive session of Claude Code does not load any user-configured MCP servers (neither from a project-level .mcp.json file nor from the global configuration set by claude mcp commands). The /mcp command shows 'No MCP servers configured', while the external claude mcp list command correctly shows connected servers. Debug logs confirm that only the built-in 'ide' MCP server is connected, with no attempts to load any others."

I think it's all in beta, not worth to waste time yet on this.

Starting Claude with --mcp-config /home/user/project-dir/.claude/settings.json shows the mcp server in Ubuntu 24.04. Without the said flag and path specification, the project MCP server doesn't get found.

I had the same issue and saw this lines on .claude\settings.local.json on my local folder, deleting them made CC aware of the MCPs

"disabledMcpjsonServers": [
"supabase",
"chrome-devtools"
]

Thanks, I'll try that asap!

Il giorno sab 2 ago 2025 alle ore 12:28 spidey000 @.***>
ha scritto:

spidey000 left a comment (anthropics/claude-code#1611) <https://github.com/anthropics/claude-code/issues/1611#issuecomment-3146421022> I had the same issue and saw this lines on .claude\settings.local.json on my local folder, deleting them made CC aware of the MCPs "disabledMcpjsonServers": [ "supabase", "chrome-devtools" ] — Reply to this email directly, view it on GitHub <https://github.com/anthropics/claude-code/issues/1611#issuecomment-3146421022>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AACHMZCVNWKMEZYNREOKXKD3LSHDVAVCNFSM6AAAAAB6T5OXQGVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZTCNBWGQZDCMBSGI> . You are receiving this because you commented.Message ID: @.***>

sad to see claude is that buggy. wasted hours with no solution.

I'm having a similar but not quite identical issue, dropping a comment here in case it helps:

I've built an MCP server for my specific project, and set it up in .mcp.json. Claude Code sees the server, but it sees no capabilities, and as a result doesn't show any tools. I can't really install this server globally to tell if the local/global distinction makes a difference because it's very specific to my project and in fact actually detects when it's running from the target/ directory to enable debug mode.

The server seems to run fine. Claude wrote most of the server itself. If I manually send the capability/tool listing requests from the spec, things look fine. Claude even wrote a bunch of test shell and Python scripts to test the MCP server and claims the bug is on your end. :)

So this isn't quite the server not working--it shows as connected, but with no capabilities and thus no tools.

I'll note that initially the capabilities were empty until I discovered that they needed to contain "tools". I don't know if there's any caching happening--maybe my server is still referenced as exposing no tools even though I've fixed that bug on my end--but I've searched all the JSON config files I could find in my project/~/.claude* and didn't find anything obvious.

I also have the Puppeteer MCP server installed globally and it works fine. Unfortunately again, I can't install this one globally because it's specific to my project.

Make sure you kill all prior Claude tasks before restarting the MCP server. This had me stumped for a few hours yesterday. This Youtube video was helpful - https://www.youtube.com/watch?v=xcj_5xl1RNs&t=36s

Got it working finally. Lots of steps, including needing to run the outlook-auth-server.js locally via node.exe and open port 3333 to the internal network on the Windows firewall. I used Claude to help me troubleshoot and it saved a whole lot of time.

Here is the MCP project I used to connect Outlook / M365 to Claude - https://github.com/ryaker/outlook-mcp

Disclaimer - I have been in tech since 1983 but never became a coder. Currently in working in cybersecurity.

claude --debug

helped me figure it out that i was missing docker

[ERROR] MCP server "github" Connection failed: Executable not found in $PATH: "docker"
[DEBUG] MCP server "github": Connection attempt completed in 11ms - status: failed
[DEBUG] Creating shell snapshot for zsh (/bin/zsh)

I'm having the same issue.

<img width="1350" height="334" alt="Image" src="https://github.com/user-attachments/assets/6cf14462-5ce7-4a91-8a48-2d9031cbbbc2" />

<img width="836" height="352" alt="Image" src="https://github.com/user-attachments/assets/186c0f36-48d1-42a2-bc1b-9a3c5ff8c7d8" />

I keep getting: Error: Not connected

And no. the issue is NOT my backend it is working via swagger etc.

#!/usr/bin/env python3
"""
Cheat Engine MCP Server
Provides tools to interact with Cheat Engine via REST API
"""

from mcp.server.fastmcp import FastMCP
import httpx
import os
from typing import Dict, Any

mcp = FastMCP(name="Cheat Engine Server")

CHEAT_ENGINE_HOST = os.getenv("MCP_HOST", "localhost")
CHEAT_ENGINE_PORT = int(os.getenv("MCP_PORT", "6300"))
CHEAT_ENGINE_BASE_URL = f"http://{CHEAT_ENGINE_HOST}:{CHEAT_ENGINE_PORT}"

@mcp.tool()
async def execute_lua(code: str) -> Dict[str, Any]:
    """
    Execute Lua code in Cheat Engine
    
    Args:
        code: The Lua code to execute
        
    Returns:
        Dictionary with result and success status
    """
    async with httpx.AsyncClient() as client:
        try:
            response = await client.post(
                f"{CHEAT_ENGINE_BASE_URL}/api/cheatengine/execute-lua",
                json={"code": code},
                timeout=30.0
            )
            response.raise_for_status()
            return response.json()
        except httpx.RequestError as e:
            return {"result": f"Request failed: {e}", "success": False}
        except httpx.HTTPStatusError as e:
            return {"result": f"HTTP error: {e.response.status_code}", "success": False}

@mcp.tool()
async def get_process_list() -> Dict[str, Any]:
    """
    Get list of running processes from Cheat Engine
    
    Returns:
        Dictionary with process list and success status
    """
    async with httpx.AsyncClient() as client:
        try:
            response = await client.get(
                f"{CHEAT_ENGINE_BASE_URL}/api/cheatengine/process-list",
                timeout=30.0
            )
            response.raise_for_status()
            return response.json()
        except httpx.RequestError as e:
            return {"process_list": None, "success": False, "error": f"Request failed: {e}"}
        except httpx.HTTPStatusError as e:
            return {"process_list": None, "success": False, "error": f"HTTP error: {e.response.status_code}"}

@mcp.tool() 
async def get_api_info() -> Dict[str, Any]:
    """
    Get information about the Cheat Engine REST API
    
    Returns:
        API information and available endpoints
    """
    return {
        "base_url": CHEAT_ENGINE_BASE_URL,
        "swagger_ui": f"{CHEAT_ENGINE_BASE_URL}/swagger",
        "description": "REST API for Cheat Engine MCP Server"
    }

if __name__ == "__main__":
    # Run as MCP server using stdin/stdout
    mcp.run()

<img width="1158" height="1116" alt="Image" src="https://github.com/user-attachments/assets/8dec660c-b7c5-4269-8173-72d2d83517d4" />

As you can see my swagger is working perfectly so idk what the issue is.

EDIT: Of course it works when I start claude via --debug. Of course!!!!!

For folks hitting similar issues, debug by:

1. Running /mcp to verify whether your MCP server is found, and what its current status is
2. Running Claude Code in debug mode (claude --debug) for more detailed MCP error output during startup

Closing this issue. Please feel free to open a new issue if the steps above don't help.

This issue has been automatically locked since it was closed and has not had any activity for 7 days. If you're experiencing a similar issue, please file a new issue and reference this one if it's relevant.