VS Code silently ignores MCP configs written for Cursor due to a single key name difference

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A developer lost an hour debugging a seemingly broken MCP server, only to discover VS Code had quietly ignored the entire configuration file. The root cause is a single key name difference: tools like Cursor, Windsurf, and Claude Desktop use a top-level 'mcpServers' key, while VS Code requires 'servers'. Because the file remains valid JSON, VS Code parses it without error, finds no recognised key, and registers no MCP servers — producing no warning, no log entry, and no visual indication of failure. Most MCP configuration snippets found in blogs and quickstart guides are written for Cursor, which popularised its format early, making it easy to paste an incompatible config into VS Code unknowingly. The author advises always sourcing config snippets from documentation written specifically for the client in use, rather than adapting them from another tool.

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ProgrammingDEV Community ·

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ProgrammingDEV Community ·

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ProgrammingDEV Community ·

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