You’ve got one AI agent fixing a bug, another writing tests for a module nobody’s touched in months, and a third exploring whether a refactor is even worth doing — and you’re switching between three terminal tabs, losing track of which one printed which error, and manually copying diffs into a text editor just to see what actually changed. Running one agent at a time is easy. Running several at once, safely, is a different problem entirely.
Running AI coding agents in parallel means giving each one an isolated, independent copy of your repository to work in — its own branch, its own files on disk — so that five agents running simultaneously produce five clean, reviewable diffs instead of one tangled mess. Get the isolation right, and parallel agents feel like delegating to a small team. Skip it, and you get file conflicts, phantom bugs, and diffs you can’t trust.
Why “Just Open More Terminal Tabs” Doesn’t Scale
The naive approach — a terminal tab per agent, all pointed at the same checked-out repo — breaks down fast:
- File collisions. Two agents editing the same working directory can overwrite each other’s uncommitted changes without either one knowing.
- No clean diff. When everything happens in one working copy, you can’t tell which agent produced which change without mentally untangling it yourself.
- Context switching cost. Remembering which of fifteen tabs is running which task, on which branch, against which repo, becomes its own job.
- No safe undo. If one agent goes sideways, discarding its work means carefully reverting specific files rather than just throwing away a folder.
The fix for all four is the same: one isolated workspace per agent, with a way to see what each one produced before it touches anything shared.
The Workflow: Isolate, Run, Review, Ship
1. Give each agent its own git worktree and branch
A git worktree checks out a branch into its own folder while sharing history with your main repo — so agent A can be mid-edit in one folder while agent B runs entirely undisturbed in another, and neither can step on your own uncommitted work. This is the single most important habit for running agents in parallel; without it, everything downstream gets shakier.
2. Run the agents
With isolation in place, kick off however many sessions you can meaningfully track — a bug fix here, a test-writing task there, an exploratory refactor somewhere else. Each one works inside its own worktree, so their tool calls, file edits, and test runs are fully independent.
3. Review each one with a diff panel, not a mental model
Once a session finishes (or you want to check in mid-task), pull up the diff — file by file — before deciding what to do with it. This is where vibe coding either stays trustworthy or stops being trustworthy: the diff is the evidence, the agent’s own summary is just a claim.
4. Open the result in your actual editor
When a change looks promising but you want to poke around properly — trace a call, run something interactively, check a type — jump straight into VS Code, Cursor, or Xcode on that specific worktree folder, without losing track of which session it came from.
5. Merge what earns it, discard the rest
Because each agent lived in its own worktree, discarding a session that didn’t pan out is just deleting a folder and a branch — nothing else is affected.
How Agents Puts This Whole Workflow in One Sidebar
Agents is a macOS app built around exactly this loop — “lightweight terminals for vibe coding,” designed for developers running Claude Code or similar tools across more than one task at a time.
| Step in the workflow | What Agents does |
|---|---|
| Isolate | Every session automatically checks out its own git worktree and branch — no manual git worktree add |
| Organize | Workspaces hold your repos; sessions (the branches you’re running agents on) nest underneath in one sidebar |
| Run | GPU-accelerated terminals via libghostty — adjustable opacity, custom backgrounds, a per-terminal command palette, fast even with a wall of panes open |
| Review | A right-side, Cursor-style git diff panel shows exactly what each agent changed, with copyable file:line references |
| Capture | Built-in screenshots — capture any window, annotate, crop, export, with unlimited history — handy for grabbing a UI result or an error dialog mid-session |
| Hand off | One click opens the workspace or worktree folder in VS Code, Cursor, or Xcode |
The core idea: instead of a terminal tab per agent and a mental map of which branch is which, you get a sidebar where every session is already isolated, already diffable, and already one click from your editor.
A Concrete Example
Say you’re tackling three unrelated tickets at once — a rate-limiting bug, a missing test suite, and a dependency bump. In Agents, that’s three sessions under one workspace:
- Session “rate-limit-fix” — its own worktree, its own branch, an agent working through the bug with a reproduction test.
- Session “add-checkout-tests” — a separate worktree, an agent writing coverage for the checkout module.
- Session “bump-deps” — a third worktree, an agent working through a dependency upgrade and fixing whatever breaks.
Each one runs independently. You check the diff panel on whichever session finishes first, copy a file:line reference back into the agent if something needs a fix, and merge each branch on its own timeline — no coordination required between them because none of them ever shared a working directory.
How Many Agents Is “Too Many”?
There’s no fixed number — it depends on how much reviewing bandwidth you actually have, not how many terminals you can technically open. A useful rule of thumb: run as many agents in parallel as you can comfortably review the diffs for within the time it takes them to finish. For most developers that’s somewhere between two and five sessions at once — enough to make real progress on several fronts, not so many that “review the diff” turns into “skim the diff,” which defeats the point of isolating them carefully in the first place.
It also helps to mix task types rather than running five similar tasks at once. A bug fix, a test-writing task, and a dependency bump draw on different parts of the codebase and rarely produce diffs that are hard to tell apart — which keeps review fast even as the number of parallel sessions grows.
Getting Started
- Pick two or three small, independent tasks you’d normally do one after another.
- Give each one its own git worktree and branch instead of running them sequentially in the same checkout.
- Review each diff on its own terms before merging — don’t let “tests passed” substitute for actually reading the change.
- If you’re on macOS, download Agents and open two or three sessions side by side — it’s a one-time $9.99, with a 7-day free trial to see whether running a small fleet of agents actually fits how you work.
Running one AI agent at a time is comfortable. Running several, safely, just takes the right isolation and a place to actually review what each one produced — and that combination is what turns “a few agents running somewhere” into a fleet you can actually trust.