MCP error fixes
Exact error text, the cause, and a fix you can paste. Every guide cites official docs and real GitHub issues.
MCP server not showing in Cursor (or showing a red dot)
No tools available • Client closed • red status dot next to the server in Cursor's MCP settings
MCP server not showing in Claude Desktop
No hammer/tools icon appears, or "Could not attach to MCP server" / "MCP server failed" in Claude De
Fix "spawn npx ENOENT" when starting an MCP server
Error: spawn npx ENOENT
MCP servers fail on Windows with npx (use cmd /c)
spawn npx ENOENT • 'npx' is not recognized • Connection closed (Windows only)
MCP server can't see my API key (env vars not passed)
401 Unauthorized • "API key is required" • "Missing environment variable"
MCP config JSON syntax errors (trailing commas, comments, quotes)
Unexpected token } in JSON at position … • "Failed to parse MCP config" • servers silently missing
Too many MCP tools: tool limits in Windsurf, Cursor and VS Code
Tool limit warnings, or the agent ignoring tools from a server you enabled
Fix "spawn uvx ENOENT" for Python MCP servers
Error: spawn uvx ENOENT
"MCP error -32000: Connection closed": what it means and how to fix it
McpError: MCP error -32000: Connection closed
"MCP error -32001: Request timed out"
McpError: MCP error -32001: Request timed out
"Unexpected token … is not valid JSON" from a custom MCP server
SyntaxError: Unexpected token 'S', "Server sta"... is not valid JSON
MCP server crashes because the client uses an old Node version
SyntaxError: Unexpected token '?' • ReferenceError: fetch is not defined • ERR_REQUIRE_ESM
Claude Code: MCP server added but not available ("No MCP servers configured")
No MCP servers configured • server missing from /mcp in another folder
VS Code ignores my MCP config ("servers" vs "mcpServers")
Server does not appear in the MCP: List Servers view; config copied from Cursor/Claude does nothing
GitHub MCP server: "Bad credentials" / 401 errors
401 Bad credentials • "GITHUB_PERSONAL_ACCESS_TOKEN not set"
Windsurf: MCP server not loading in Cascade (mcp_config.json location)
Server missing from Cascade's MCP list or shown as errored after editing mcp_config.json