Head to head · Agent harnesses · October 2026 research run

Emdash vs Unstoppable

Emdash scores 53.9 (D) on agent readiness against Unstoppable's 34.7 (F), and leads in 6 of 7 scored categories. Both do agent harnesses.

Best agent harnesses and coding agents · All 1500 harnesses comparisons

Which one, for what

Emdash D

Best for Developers who want parallel agents in worktrees, fed from their issue tracker, locally or over SSH.

Ahead on

  • Reliability, 55 against 45
  • Schema & documentation, 55 against 30
  • Agent ergonomics, 55 against 5
  • Payments & pricing, 60 against 30
  • Maintenance & community, 70 against 58

Also in its favour

  • Open source

Watch for

Telemetry on unless turned off in Settings or with TELEMETRY_ENABLED=false

Unstoppable F

Best for A developer who runs Claude Code, Codex and Cursor on existing plans and wants parallel worktrees, pipelines and phone check-ins in one app.

Also in its favour

  • Free to start without a card

Watch for

No API, MCP server, SDK or documented CLI for an outside agent. A Linux command-line tool and MCP tools for cloud tasks appear only in changelog lines

Why the edge

Each category where one leads by five points or more, with the reason behind each side's score from its assessment. The numbers are in the table below; this is what they stand for.

Agent ergonomics Emdash +50

Emdash 55

Harness reading. Issue intake from Linear, GitHub, Jira and others, diff review, pull requests and CI checks in one place, local or over SSH (55).

Unstoppable 5

These lines measure an interface an agent calls, and Unstoppable has none, so context cost, output controls and retries score nothing. For the person, a usage limit shows choices to wait for the reset or continue on credits (2 of 20). Guest use with no account, a first-run page that imports Claude and Codex projects, and few required settings. No SDK (3 of 15). Total 5.

Payments & pricing Emdash +30

Emdash 60

Free self-hosted software with nothing to buy, so 0 for a protocol and 20 each for public pricing, a free tier and onboarding with no sign-up, 60.

Unstoppable 30

No x402, MPP or L402 (0). The app is published as free, but AI credit prices appear only after sign-in, and no pricing page exists (unstoppable.ai/pricing redirects to the home page). Plan prices of $19, $29 and $49 appear only in an 11 August 2026 blog post (10). Guest use with no account, and 10 free AI credits a day with no card (20). A person has to download and install the app, so no autonomous onboarding (0). Total 30.

Schema & documentation Emdash +25

Emdash 55

Harness reading. Docs site and a workspace server package (55).

Unstoppable 30

Graded on the interface an outside agent can use, which is none. No API, OpenAPI file, MCP server or documented command (0). unstoppable.ai/llms.txt lists the product, help and policy pages in Markdown (10). Twenty-two dated help articles explain for a person what each part does and when to use it, such as Code and Work modes and approval modes (5 of 20). No typed inputs an agent could call (0). Step-by-step examples for people and named error states such as usage limit reached and update failed, with no error responses for an agent (3 of 15). Numbered versions and a public dated changelog, which lists only four releases from 20 to 23 October 2026 (12 of 15). Total 30.

Maintenance & community Emdash +12

Emdash 70

v1.2.11 on 6 November 2026 (30). v1.2.9, v1.2.10 and v1.2.11 within two weeks (20). GitHub issues and pull requests weren't read (GitHub's pages refuse these sessions), so that line is scored absent (0). Current installers and Homebrew cask (15). Release workflows, no test CI (5). 30 + 20 + 0 + 15 + 5 = 70.

Unstoppable 58

Read for a closed product. Version 1.15.0 on 23 October 2026, and iOS 1.1.9 on 27 October (30). Four desktop releases from 20 to 23 October and nine iOS updates since 11 August 2026 (20). A public changelog, a support email, in-app feedback and a Discord server, none tested for replies. Help articles were updated between 19 and 24 October (6 of 15). No SDK and no MCP registry entry (0). Windows updates check signatures per the 1.13.0 notes, with no build pipeline to inspect (2 of 10). Total 58.

Reliability Emdash +10

Emdash 55

Local software. Homebrew cask and installers for macOS, Windows and Linux (20). A code-consistency check and release workflows; no test workflow found (10). GitHub issues and pull requests weren't read (GitHub's pages refuse these sessions), so that line is scored absent (0). Stable tags to v1.2.11, release notes on GitHub (10). Version 1.2.11 (15). 20 + 10 + 0 + 10 + 15 = 55.

Unstoppable 45

Read as local software, because the product is the desktop app the owner runs, as for the other harnesses. Signed downloads for macOS Apple Silicon, macOS Intel and Windows on the download page, version 1.15.0, plus iOS and Android apps in the stores, with the supported platforms stated. No package registry (20). Closed source with no public CI or test suite (0). No public issue tracker. Bugs go through in-app feedback, email and Discord, none of which shows a record we could read (0). Version numbers and a dated changelog, but only 1.12.0 to 1.15.0 are listed and breaking changes are not marked as such (10). Version 1.15.0 (15). The hosted parts (accounts, AI credits, cloud agents, Remote Control) have no status page. status.unstoppabledomains.com covers the domains business only.

Score by category

CategoryWeight this runEmdashUnstoppableEdge
Reliability16%205545Emdash +10
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.25530Emdash +25
Agent ergonomics13%16.2555Emdash +50
Security & auth14%17.53836Emdash +2
Payments & pricing10%12.56030Emdash +30
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.87058Emdash +12
Transparency & trust7%8.85456Unstoppable +2
Negative events≤1500
TotalD 53.9/100F 34.7/100

Facts side by side

FactEmdashUnstoppable
KindAgent harnessAgent harness
VendorGeneral Action, Inc.Unstoppable Domains, Inc.
Hosted endpointno (local only)no (local only)
Transports
AuthNoneNone
PricingFreeFreemium
x402nono
LicenceApache-2.0Proprietary, under Unstoppable Domains, Inc.'s Terms of Service. No source published
Read-only variant documentednono
llms.txtnoyes
Last release2026-11-062026-10-23
Terms last updatedno document linked2026-10-06
Privacy policy last updatedno document linked2026-10-08
Customer content may train modelsnot read yetnot found in the text
Terms restrict automated accessnot read yetnot found in the text
Terms restrict benchmarkingnot read yetyes
Terms or service can change without noticenot read yetnot found in the text
Arbitration or class-action waivernot read yetyes

How the scores have moved

Emdash

No score change since it was listed.

Unstoppable

Verdicts

Emdash

A mature open-source app for parallel coding agents in Git worktrees, with issue intake from a dozen trackers and remote machines over SSH. Telemetry is on unless you turn it off, and no test workflow was found in the repository.

Unstoppable

Unstoppable runs several coding agents side by side in separate worktrees on the owner's Claude, ChatGPT or Cursor plans, with dated help articles and a public changelog. It has no API, MCP server or documented command an outside agent can call, every chat starts in Full access, and its pages disagree on which parts need a paid plan.

Before you call either

Emdash

  1. Launch with TELEMETRY_ENABLED=false if you don't want telemetry
  2. Use the SSH mode to keep agents on a remote machine

Unstoppable

  1. Don't plan to drive Unstoppable from another agent. It has no documented API, MCP server or CLI. Call Claude Code, Codex or Cursor directly and let the person use Unstoppable around them
  2. Inside Unstoppable, check the approval mode before acting. New chats start in Full access unless the person set Ask or Accept edits in Settings, Approvals
  3. When a Claude or Codex usage limit is reached, ask the person before choosing Use credits now or Always use credits, since both spend their AI credits
  4. Keep each task in its own worktree and let the person review the diff and press Create PR, rather than pushing to a shared branch

Questions

Which is better for AI agents, Emdash or Unstoppable?

Emdash scores 53.9 (D) on agent readiness against Unstoppable's 34.7 (F), and leads in 6 of 7 scored categories.

Are Emdash and Unstoppable open source?

Emdash is open source (Apache-2.0). No open-source release is listed for Unstoppable.

Other comparisons with Emdash or Unstoppable

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