---
title: "Running several coding agents in parallel"
url: https://helicon.sh/use-cases/parallel-agents
description: "Isolated worktrees, one sidebar, and clear marks for which thread is running, finished, or blocked on you. Plus the cost of all that parallelism, per thread."
updated: 2026-09-19
site: Helicon
---

# When you run more agents than you can watch

Parallelism breaks down at the interface, not the agent. Four threads means four places something can be waiting. Helicon puts every thread in one sidebar grouped by working directory, marks which are running and which are blocked on an approval, and shows what the fan out cost per thread.

## Isolation first

Two agents on one checkout will fight. Give each task an isolated git worktree, add each as a project, and the collisions stop being possible rather than being unlikely.

```sh
git worktree add ../proj-auth -b feat/auth
git worktree add ../proj-search -b feat/search
```

## Then triage

| Signal | What you do |
| --- | --- |
| Thread marked running | Leave it |
| Thread marked blocked | Open it, read the request, decide |
| Thread finished | Review the diffs in the thread |
| Tool call stuck | Background it, stop it, or stop everything |

## Then count the cost

Fan out spends tokens faster than sequential work, which is the whole point and also the risk. The usage page breaks cost down by thread, by day and by model, so the tradeoff between wall clock time and spend is visible instead of assumed.

## Frequently asked questions

### How many threads is too many?

The limit is usually your attention rather than the machine. The sidebar exists so the number you can supervise is higher than the number you can remember.

### Do worktrees appear separately?

Yes, each as its own project with a badge, because each is its own working directory.

### Can I stop everything at once?

Yes, and it ends running calls without ending the sessions.

## Related

- [Parallel agents in worktrees](https://helicon.sh/guides/run-parallel-agents): Use isolated git worktrees so parallel agents never collide, then watch all of them from one sidebar that shows which threads are running and which are blocked.
- [Projects and worktrees](https://helicon.sh/features/projects-and-worktrees): Helicon groups every Muse Code thread under the directory the agent worked in, isolated git worktrees included, so parallel work across repositories has one place to live.
- [Subagents and workflows](https://helicon.sh/features/subagents-and-workflows): Parallel subagents and workflow runs are hard to follow in a terminal. Helicon shows them as structure: what is running, what finished, and what you can cancel or retry.

---

Helicon is a free, MIT licensed, unofficial community client for Meta's Muse Code CLI. Not made, sponsored or endorsed by Meta. Source: https://helicon.sh/. Machine readable index: https://helicon.sh/llms.txt