Busabase × CursorKnowledge base for Cursor
Keep instructions close to the code. Keep decisions, evidence, and ownership in a reviewed record that survives branches, editors, and handoffs.
Rules are instructions
Cursor Rules shape behavior. They should not become a catch-all database.
Cursor documents four instruction surfaces: Project Rules, User Rules, Team Rules, and AGENTS.md. They are designed to guide Agent at prompt time. A team decision has a different job: it needs evidence, an owner, a date, and a visible review history.
| Instruction surface | Scope | Keep here |
|---|---|---|
| Project Rules | Repository and file patterns | Architecture conventions and recurring workflows |
| User Rules | One developer's Cursor environment | Personal preferences and interaction style |
| Team Rules | A managed Cursor team | Organization-wide Agent behavior |
| AGENTS.md | Repository tree | Readable operating instructions near the code |
The ownership boundary
A rule says what Cursor should do. A record says what the team accepted.
Mixing the two makes both weaker. Instructions become bloated with history, while decisions lose the fields that make them reviewable. Use a small promotion test before moving anything out of chat or a branch.
Where drift begins
The same repository can produce three different versions of ‘what we decided.’
Local Agent sessions, long-lived branches, and adjacent repositories often carry different assumptions. The code may still compile while the product, support, or operations team is acting on an older decision.
Decision register
Store the minimum fields the next Cursor session needs to trust.
A compact Base is easier to maintain than a growing project notebook. It separates the decision from its evidence and makes staleness visible.
| Field | Question it answers |
|---|---|
| decision | What may the team rely on? |
| scope | Which repository, service, or customer does it affect? |
| evidence | Which test, link, or record supports it? |
| owner | Who keeps the decision current? |
| effective_from | When did it begin to apply? |
| revisit_when | What would reopen the decision? |
Review loop
Let Cursor propose the update without silently rewriting project truth.
Cursor can read accepted records for the task at hand. When a durable decision changes, it submits a Change Request. The reviewer sees the field-level difference and decides whether the new value should become canonical.
Read the accepted decision
Work against the current repository
Propose changed fields with evidence
Review and merge the canonical record
Connection stays separate
This page defines what to remember, not how to edit mcp.json.
Use the existing connection guide for global or project-scoped MCP setup and OAuth. Cursor's official Rules documentation explains how instruction scopes work; Busabase handles the reviewed record that those rules may point to.
Questions before adoption
Cursor knowledge base FAQ
Does Busabase replace .cursor/rules or AGENTS.md?
No. Keep Agent instructions in Cursor Rules or AGENTS.md. Use Busabase for reviewed facts and decisions that need owners, sources, and reuse beyond one repository context.
Should every Cursor finding become a record?
No. Promote only information another person or Agent will rely on later. Scratch analysis, speculative notes, and one-off debugging output should remain temporary.
Can Cursor update a decision register?
Yes, within the granted permission level. For shared knowledge, give it Change Request permission so it can propose field changes while a reviewer controls the merge.
What belongs in Git instead?
Code, tests, migrations, repository instructions, and implementation-owned documentation should remain in Git. Busabase is useful when the same decision also guides other repositories or business systems.
Can one Base support several repositories?
Yes. Add an explicit scope field and keep evidence links precise. That makes cross-repository reuse possible without pretending every decision applies everywhere.
Start with the decision that keeps drifting
Give the next Cursor session an accepted answer, not another old chat.
Create one small decision register, connect Cursor, and review the first proposed correction before anyone reuses it.