I am guessing for integrating the MCP server locally you might have run some form of the code :

claude mcp add sequential-thinking -s user -- npx -y @modelcontextprotocol/server-sequential-thinking

The npx command is what runs the node process. You can try adding the --use-system-ca just after npx and if certs are setup correctly it should work.

If this is not the command please share the command that you are using to add the mcp to claude code?