Prompts
Why does Cursor's Agent mode keep editing files you never mentioned?
Cursor's Agent mode can genuinely build a multi-file feature — but only if the brief actually constrains scope. Left vague, it wanders, and reviewing a diff that touched twice as many files as expected is a worse outcome than writing the constraint upfront.
Last updated Aug 15 · 11 min read
Why Agent mode specifically needs tighter briefs than chat
Asking a chat assistant a question and asking an agentic editor to build a feature are different categories of request — Agent mode can actually touch your filesystem, and a loosely scoped brief gives it room to wander into files you never intended to change. The Cursor prompt library is written specifically with the constraint blocks that stop that from happening, not generic feature descriptions.
The foundational entry, briefing Cursor's Agent mode to build a multi-file feature without wandering into untouched files, is built around explicitly naming which files are in scope and, just as importantly, which are explicitly out of scope — the second half is what most hand-written briefs skip.
Cmd+K: keeping an inline edit actually inline
A related, smaller-scale version of the same problem: Cmd+K inline edits sometimes rewrite more of a block than intended, when the instruction was meant to change only the highlighted lines. Forcing Cmd+K to change only the highlighted lines, not the whole block around them addresses this directly with an explicit scope constraint in the instruction itself.
BugBot and checkpoints: review and rollback, not just generation
Cursor BugBot reviewing a PR benefits from being pointed at the actual risk rather than a generic full-diff pass — pointing BugBot at the real risk in a PR instead of a generic scan does exactly that. And Agent mode's checkpoints — snapshots taken during a session — become a genuine safety net for a risky refactor only if you actually plan to use them as one; turning Agent-mode checkpoints into a real rollback plan treats them as a deliberate strategy rather than an incidental feature.
Monorepos, design mocks, and spec-driven tests
In a multi-root monorepo workspace, telling Cursor which package actually owns a given change avoids edits leaking across package boundaries that were never meant to be touched together — the specific problem that prompt addresses. For design work, turning a pasted design screenshot into a component built from your existing design system keeps a generated component consistent with what already exists rather than inventing new patterns. And for testing, having Agent mode write tests against the actual spec rather than against whatever the code already does avoids the circular trap of tests that just confirm existing (possibly buggy) behaviour.
Dependency upgrades and self-auditing scope creep
A major dependency upgrade benefits from explicit staging — triage what needs to change, migrate it, then verify — rather than one enormous, hard-to-review commit; running a major dependency upgrade through Agent mode in triage-migrate-verify stages is built around that staged structure. And one prompt turns the scope-creep problem back on the agent itself: making Agent mode audit its own diff for scope creep before you review it catches wandering changes before a human reviewer has to.
Notepads: writing the brief once for a task that recurs
For a task that comes up repeatedly with the same shape, a Cursor Notepad written once removes the need to re-explain the brief every time — building a Notepad once with reusable context so a recurring task stops needing a re-explained brief is the template for setting that up properly the first time.
When Cursor is one part of a bigger engineering setup
Good briefs make Agent mode reliable for individual tasks. Configuring a whole team's Cursor workflow — shared rules, consistent conventions across a codebase — is a bigger setup question. That's the kind of engineering process work Scult's software team helps with, or book a meeting to talk through your team's setup.
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The free tools and prompts on this site handle the small, solved problems. If what you need is bigger — custom software, built and maintained for you — that's Scult's day job.
