Filesystem MCP writes hang intermittently for 4 minutes then time out with unresponsive when launched via npx -y

What this error means

edit_file hangs for 4 minutes, then times out with 'unresponsive' — only when Filesystem MCP configured via command: npx args: [-y, @modelcontextprotocol/server-filesystem] is a Claude Code failure pattern reported for developers trying to fix intermittent mcp write hangs that block claude code desktop editing operations; reads work fine but writes fail. hypothesis: npx re-resolving package each stdio handshake causes race condition with claude desktop startup window.. Based on the imported evidence, treat this as a tool-specific troubleshooting page rather than a generic API error.

Why this happens

GitHub Issue #4026 on modelcontextprotocol/servers (opened Apr 23, 2026). macOS-specific with Node.js v22. Works reliably after switching to npm install -g + direct binary path. Labeled as bug. Affected users following official docs get broken experience. High commercial value for Claude Code/Claude Desktop subscribers.

Common causes

• GitHub Issue #4026 on modelcontextprotocol/servers (opened Apr 23, 2026). macOS-specific with Node.js v22. Works reliably after switching to npm install -g + direct binary path. Labeled as bug. Affected users following official docs get broken experience. High commercial value for Claude Code/Claude Desktop subscribers.

Quick fixes

1. Confirm the exact error signature matches edit_file hangs for 4 minutes, then times out with 'unresponsive' — only when Filesystem MCP configured via command: npx args: [-y, @modelcontextprotocol/server-filesystem].
2. Check the Claude Code account, local tool state, and provider configuration involved in the failing workflow.
3. Compare the failing environment with a known working setup, then change one configuration value at a time.

Platform/tool-specific checks

• Verify the command, editor, extension, or API client that produced the error.
• Compare local settings with CI, deployment, or editor-level settings when the error appears in only one environment.
• Avoid deleting credentials, local model data, or project settings until the failing scope is clear.

Step-by-step troubleshooting

1. Capture the exact error message and the command, editor action, or request that triggered it.
2. Check whether the failure is account/auth, quota/rate, model/provider, local runtime, or deployment configuration.
3. Review the source evidence below and compare it with your environment.
4. Apply one change at a time and rerun the smallest failing action.
5. Keep the working fix documented for the team or deployment environment.

How to prevent it

• Keep provider/tool configuration documented.
• Record non-secret diagnostics such as tool version, provider name, model name, and command path.
• Add a lightweight check before CI or production workflows depend on the tool.

Sources checked

• https://github.com/modelcontextprotocol/servers/issues/4026

Evidence note: GitHub Issue #4026 on modelcontextprotocol/servers (opened Apr 23, 2026). macOS-specific with Node.js v22. Works reliably after switching to npm install -g + direct binary path. Labeled as bug. Affected users following official docs get broken experience. High commercial value for Claude Code/Claude Desktop subscribers.

Related errors

• AI Coding Tools

FAQ

What should I check first?

Start with the exact edit_file hangs for 4 minutes, then times out with 'unresponsive' — only when Filesystem MCP configured via command: npx args: [-y, @modelcontextprotocol/server-filesystem] text and the smallest action that reproduces it.

Can I ignore this error?

No. Treat it as a failed Claude Code workflow until the root cause is understood.

Is this guaranteed to have one fix?

No. The imported evidence supports the troubleshooting path above, but tool behavior can vary by account, plan, version, provider, and local configuration.

How do I know the fix worked?

Rerun the same command, editor action, or request. The fix is working when that action completes without edit_file hangs for 4 minutes, then times out with 'unresponsive' — only when Filesystem MCP configured via command: npx args: [-y, @modelcontextprotocol/server-filesystem].