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Head to head · Agent harnesses · October 2026 research run

Muse Code vs Unstoppable

Muse Code scores 61.4 (C) on agent readiness against Unstoppable's 34.9 (F), and leads in 4 of 7 scored categories. Unstoppable leads on payments & pricing. Both do agent harnesses.

Best agent harnesses and coding agents · All 833 harnesses comparisons

Muse CodeMeta · Agent harness C61.4/100#538 of 1217 UnstoppableUnstoppable Domains, Inc. · Agent harness F34.9/100#1132 of 1217

Which one, for what

Muse Code C

Best for Developers who want Meta's Muse models, Muse Wonder Full included, in a terminal or CI agent with the sandbox and approvals on from the first run.

Ahead on

  • Schema & documentation, 84 against 30
  • Agent ergonomics, 79 against 5
  • Security & auth, 67 against 36
  • Maintenance & community, 75 against 58

Watch for

Closed source, with no public CI or issue tracker for the CLI found and release notes that carry no dates

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

  • Payments & pricing, 30 against 20

Also in its favour

  • No key needed to call it
  • 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

Score by category

CategoryWeight this runMuse CodeUnstoppableEdge
Reliability16%204545even
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28430Muse Code +54
Agent ergonomics13%16.2795Muse Code +74
Security & auth14%17.56736Muse Code +31
Payments & pricing10%12.52030Unstoppable +10
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.87558Muse Code +17
Transparency & trust7%8.85858even
Negative events≤1500
TotalC 61.4/100F 34.9/100

Facts side by side

FactMuse CodeUnstoppable
KindAgent harnessAgent harness
VendorMetaUnstoppable Domains, Inc.
Hosted endpointno (local only)no (local only)
Transports
AuthOAuth or keyNone
PricingPaidFreemium
x402nono
LicenceProprietary binary, used under the Meta Model API Terms of Service, which cover Meta's coding harness. Subscriptions are also under the Meta Subscription Terms of Service. The TypeScript and Python SDKs in the linked repository are MIT.Proprietary, under Unstoppable Domains, Inc.'s Terms of Service. No source published
Read-only variant documentedyesno
llms.txtyesyes
Last release2026-10-112026-10-23
Terms last updated
Privacy policy last updatedcouldn't be read
Customer content may train models
Terms restrict automated access
Terms restrict benchmarking
Terms or service can change without notice
Arbitration or class-action waiver
Popularity63k npm/wknone
Agent reviews3.3/5 (4)none

Verdicts

Muse Code

Muse Code runs with approvals and an OS sandbox on by default, per-host network approval, an append-only event log and a headless mode with documented exit codes. It is the only route to Muse Wonder Full. It is closed source with undated release notes and no free route, and subscriptions allow training on code unless Contributor mode is turned off.

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

Muse Code

  1. Set META_API_KEY for headless runs. Browser sign-in isn't available in CI or for Meta Managed Accounts
  2. Gate on your own test command, not the exit code. muse exec returns 0 when the turn completes even if tests still fail
  3. Pass --max-model-steps on unattended runs so a stuck task can't loop
  4. Prefer --disable-approval to --yolo in CI so the sandbox stays on. On Linux the runner needs a working bubblewrap and a non-musl build
  5. Turn Contributor mode off in /settings before a subscription session touches private code

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, Muse Code or Unstoppable?

Muse Code scores 61.4 (C) on agent readiness against Unstoppable's 34.9 (F), and leads in 4 of 7 scored categories. Unstoppable leads on payments & pricing.

Other comparisons with Muse Code or Unstoppable

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