Head to head · Agent harnesses · October 2026 research run

T3 Code vs Unstoppable

T3 Code scores 51.9 (D) on agent readiness against Unstoppable's 34.7 (F), and leads in 4 of 7 scored categories. Unstoppable leads on transparency & trust. Both do agent harnesses.

Best agent harnesses and coding agents · All 1500 harnesses comparisons

Which one, for what

T3 Code D

Best for Developers who want one app, including on their phone, to drive several coding agents they already pay for.

Ahead on

  • Schema & documentation, 55 against 30
  • Agent ergonomics, 60 against 5
  • Payments & pricing, 60 against 30
  • Maintenance & community, 75 against 58

Also in its favour

  • Open source

Watch for

Usage data on by default, with hashed OpenAI and Claude account identifiers, and relay traces to Axiom

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.

Ahead on

  • Transparency & trust, 56 against 51

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 T3 Code +55

T3 Code 60

Harness reading. Remote control from phone or browser, portable handoffs between providers and managed policies for teams (60).

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 T3 Code +30

T3 Code 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 T3 Code +25

T3 Code 55

Harness reading. User docs in the repository (managed policy, handoffs, providers, telemetry), AGENTS.md for contributors, a server other clients connect to (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 T3 Code +17

T3 Code 75

Commits and nightly tags on 6 November 2026 (30). More than three releases in 90 days (20). GitHub issues and pull requests weren't read (GitHub's pages refuse these sessions), so that line is scored absent (0). Current official apps and install script (15). CI on push (10). 30 + 20 + 0 + 15 + 10 = 75.

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.

Transparency & trust Unstoppable +5

T3 Code 51

MIT (30). docs/user/telemetry.md lists what is sent and what isn't, but includes hashed third-party account identifiers and the README doesn't mention it (15 of 30). No deprecation policy (5). Disclosed with an opt-out, on by default (12 of 20). 30 + 15 + 5 + 12 = 62.

Unstoppable 56

Closed source under terms of 6 October 2026 that name Unstoppable Domains, Inc. and Delaware law. The terms forbid reverse engineering and building a competing product (15). The privacy policy of 8 October 2026 is written for this product. It states activity sharing levels, Off by default, secret removal and encryption, and configurable transcript retention. It gives no retention periods, names no subprocessors, and says usage telemetry may sync depending on settings, which the site's 'we don't collect your code or conversations' leaves open (16 of 30). No deprecation policy. The terms allow removing parts of the service without notice. The changelog dates one retirement (GPT 5.5 to GPT 6.1 Sol) (3 of 20). No subprocessors or data locations disclosed, and the telemetry the app sends has no documented opt-out (6 of 20). Total 40.

Score by category

CategoryWeight this runT3 CodeUnstoppableEdge
Reliability16%204345Unstoppable +2
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.25530T3 Code +25
Agent ergonomics13%16.2605T3 Code +55
Security & auth14%17.53536Unstoppable +1
Payments & pricing10%12.56030T3 Code +30
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.87558T3 Code +17
Transparency & trust7%8.85156Unstoppable +5
Negative events≤1500
TotalD 51.9/100F 34.7/100

Facts side by side

FactT3 CodeUnstoppable
KindAgent harnessAgent harness
VendorT3 Tools Inc.Unstoppable Domains, Inc.
Hosted endpointno (local only)no (local only)
Transports
AuthNoneNone
PricingFreeFreemium
x402nono
LicenceMITProprietary, 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

T3 Code

No score change since it was listed.

Unstoppable

Verdicts

T3 Code

A fast-moving open-source way to run and steer several coding agents from desktop, browser or phone, using the subscriptions you already have. It's pre-1.0, and it sends usage data by default, including hashed identifiers for your OpenAI and Claude accounts, with the opt-out documented outside the README.

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

T3 Code

  1. Set T3CODE_TELEMETRY_ENABLED=false before starting the server if you don't want usage events sent
  2. Install and log in to at least one provider CLI first, such as codex login or claude auth login
  3. Use a managed policy to fix settings across a team

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, T3 Code or Unstoppable?

T3 Code scores 51.9 (D) on agent readiness against Unstoppable's 34.7 (F), and leads in 4 of 7 scored categories. Unstoppable leads on transparency & trust.

Are T3 Code and Unstoppable open source?

T3 Code is open source (MIT). No open-source release is listed for Unstoppable.

Other comparisons with T3 Code or Unstoppable

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