MCP Config Validator
Check MCP client JSON, host compatibility and security observations locally.
Client configuration format · no protocol connection
CONFIGURATION
CONFIGURATION HEALTH
INSPECT BEFORE YOU INSTALL
Paste a configuration to check its syntax, host structure and potential security concerns.
Secret values and command arguments stay out of this summary.
Ready for local validation.
Local text inspection only. Commands, paths, URLs and annotations are untrusted data. Nothing is executed, connected, authenticated or saved.
Enable JavaScript to process locally. No server submission is available.
Inspect configuration before a host runs it.
Client configuration is not an MCP protocol message. Choose the intended host, paste strict JSON and validate its documented subset. Auto Detect distinguishes servers from mcpServers but cannot establish which host owns an ambiguous configuration.
Errors identify invalid syntax or supported structure. Warnings describe compatibility concerns. Security observations flag possible credentials, command runners and URL properties without executing or connecting to anything. A passing result cannot establish server safety.
Boundaries and formats.
Which host profiles are supported?
Cursor uses .cursor/mcp.json. VS Code uses .vscode/mcp.json with a servers root. Portable MCP here means the documented Copilot CLI / Agent Host .mcp.json subset, not a universal configuration standard. Source links and verification dates appear with host selection. Dedicated Claude Desktop validation is deferred.
What stays local?
Inputs, outputs and findings stay in browser memory. Reset and leaving the page clear workspace content. Explicit clipboard and download actions create copies under your control. Ordinary page assets still load from this site.
What are the limits?
Strict JSON only: no comments, trailing commas, duplicate keys or silently rounded numbers. Inputs are capped at 32 KiB UTF-8, 32 nesting levels and 4,000 values. Configurations permit 32 servers, 128 arguments and 64 environment/header entries per server. Conversion output is capped at 128 KiB. No remote MCP inspection is performed.