Cursor Rules vs Cursor Skills
Rules constrain. Skills teach. If you put the same text in both, you waste context and confuse the agent. Here is the split we ship.
The one-line difference
Rules (.cursor/rules/*.mdc) are passive. They fire always, or when a glob matches. Skills (.cursor/skills/*/SKILL.md) are playbooks the agent loads when the task matches the description, or when a command points at them.
Cursor's own docs now steer extension toward skills so the window stays lean. Rules remain for hard prohibitions and path-scoped law.
Use a rule when
- The instruction must apply to every turn (read CURSOR.md, tenant from session).
- The instruction should fire only on
app/api/**or*.sql. - It is a ban, not a manual: no
any, no raw SQL in the route.
Use a skill when
- The standard is longer than a screen: Stripe webhooks, RAG chunking, on-page SEO.
- You only want it loaded on matching work.
- An agent or command should open a named playbook.
Examples: Stripe payments skill, on-page SEO skill, Next.js App Router skill.
Do not duplicate
If a rule and a skill disagree, the rule wins and you have a mess. If they say the same thing, you paid twice in tokens. AgenticKit keeps a short always-on core and puts the manuals in skills. Grade a fat dump with the Rules File Grader before you migrate it.
Related pages
Frequently asked questions
Are Cursor skills replacing rules?
No. Skills are preferred for on-demand playbooks. Rules still own always-on and glob-scoped constraints.Should I migrate all .mdc files to SKILL.md?
Only the long ones. Keep tenant-from-session and error-envelope rules as rules.
See the 61 skills
The playbooks live on the Cursor Skills pillar. Rules stay short on purpose.