At my org we have been using the Figma MCP server to generate code from Figma designs. Spent about a day writing rules to keep the AI on guardrails but it's been very smooth sailing since then and any generated code needs minimal changes.
As far as rules, it's very dependent on the codebase you are working in. My recommendation for rolling something like this out is take about a day or so and try to build UI components with it, and then add to your CLAUDE.md/.clinerules/etc as the AI screws up, and there will be a ton of screw ups. Funnily enough the first rule I had to write was to tell Cline to use the MCP plugin because it kept trying to run a fresh copy and could never connect.