How to Use Design MD with Cursor

Cursor is fast at producing UI and just as fast at producing generic UI. Each new Composer session starts with no memory of your visual decisions, so developers end up re-typing the same style guidance — or worse, accepting whatever the model defaults to. The durable fix is a DESIGN.md wired into Cursor's rules system. Here is how to use design md with Cursor so every chat, Composer run, and inline edit starts from the same visual contract.

Wire it into rules, not prompts

Cursor reads rule files automatically. Two options, in order of preference:

Project rules (.cursor/rules/). Create .cursor/rules/design.mdc with a description and a glob so it activates on UI files:

---
description: Visual system constraints for all UI work
globs: ["**/*.tsx", "**/*.css"]
---
All interface work follows DESIGN.md in the repo root.
Read it before generating or editing components.
Never introduce colors, fonts, or radii not defined there.

Direct reference (@ mention). In any Composer or chat session, @DESIGN.md pins the file into context for that conversation. Use this for one-off sessions in repos where you can't add rule files.

The rules route is better because it is ambient: teammates get the constraints without knowing they exist. The question of how to use design md with Cursor is mostly the question of making the file impossible to ignore.

Shape the file for Cursor's context window

Cursor aggressively trims context, so a 4,000-word DESIGN.md may arrive truncated. Structure it so the top 80 lines carry the load:

1. Hard tokens first — palette with roles, type scale, spacing, radii, shadows.
2. Component rules second — button/input/card states in terse bullets.
3. Do's and don'ts third — the section models obey most literally.
4. Prose rationale last — humans read it; the model can lose it without harm.

If you generated the file from a real site with our generator, it already follows this order: extraction-grounded tokens up top, interpretation below.

Composer workflows

Feature scaffolding. Reference the design file and scope the task: "New /account page. Follow DESIGN.md — grayscale surfaces, single accent for interactive, cards use shadow-as-border." Composer holds constraints well when the task is one surface.

Multi-file edits. Composer's strength is coordinated changes; its weakness is drift on the later files. After a multi-file run, prompt: "Audit every file you just touched against DESIGN.md. List violations, then fix." The audit-then-fix ordering matters — it forces the model to re-read the rules before editing.

Tab completions and inline edits (Cmd+K). These see less context than Composer sessions. Keep your Tailwind theme mirrored to DESIGN.md values so even a context-blind completion picks brand tokens — the toolchain becomes the enforcement layer when the model can't see the contract.

A concrete review loop

1. Generate or edit with the design rule active.
2. Run the self-audit prompt on the diff.
3. Eyeball a screenshot against a reference page — composition errors survive token compliance.
4. When you accept an intentional deviation, write it back into DESIGN.md ("marketing pages may use the gradient hero treatment") so the exception becomes a rule instead of precedent-by-accident.

Step 4 separates teams whose design docs stay alive from teams whose docs rot. Cursor makes edits cheap; keeping the contract current is what makes them consistent.

Failure modes to expect

Rules file too vague. "Follow our design system" does nothing. Rules earn their tokens by being checkable: name the file, name the constraints, forbid inventions.

Palette without a theme. If DESIGN.md says #635BFF but your Tailwind config only knows indigo-500, completions will use the latter. Sync them once and this whole class of drift disappears.

One giant session. Long Composer conversations shed early context — including your design constraints. Prefer short sessions per surface; re-mention @DESIGN.md when a session grows.

Borrowed systems, unedited. Starting from the library is smart — shipping the Linear design md verbatim under your own logo is not. Adapt tokens to your brand, keep the structural discipline.

Starting from a real product's system

If your product doesn't have a written system yet, don't start from a blank file. Two faster paths:

• Generate from your own site. Paste your URL into the DESIGN.md generator — it extracts your real colors, fonts, spacing, and shadows and writes the file for you.
• Adapt a reference. Browse design systems by category, pick one whose feel matches your product, and swap tokens.

Either way you end up with the asset that makes how to use design md with Cursor a solved problem: a grounded, checkable file that rides along in .cursor/rules and turns every generation session into on-brand output by default.