Head to head · Agent harnesses · October 2026 research run

Agent Zero vs Muse Code

Muse Code scores 61.3 (C) on agent readiness against Agent Zero's 54.2 (C), and leads in 4 of 7 scored categories. Agent Zero leads on reliability and payments & pricing. Both do agent harnesses.

Best agent harnesses and coding agents · All 226 harnesses comparisons

Which one, for what

Agent Zero C

Best for A technical owner who wants an agent with its own Linux machine, reachable from Telegram, WhatsApp or email, with scheduled tasks and editable memory.

Ahead on

  • Reliability, 57 against 45
  • Payments & pricing, 60 against 20

Also in its favour

  • No key needed to call it
  • Open source

Watch for

No approval step before shell commands, file changes or outgoing messages. Tool Access defaults to allow

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 64
  • Agent ergonomics, 79 against 62
  • Security & auth, 67 against 54

Also in its favour

  • No incidents deducted, where Agent Zero loses 6 points for them

Watch for

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

Score by category

CategoryWeight this runAgent ZeroMuse CodeEdge
Reliability16%205745Agent Zero +12
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.26484Muse Code +20
Agent ergonomics13%16.26279Muse Code +17
Security & auth14%17.55467Muse Code +13
Payments & pricing10%12.56020Agent Zero +40
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.87575even
Transparency & trust7%8.85557Muse Code +2
Negative events≤15-60
TotalC 54.2/100C 61.3/100

Facts side by side

FactAgent ZeroMuse Code
KindAgent harnessAgent harness
VendorAgent Zero, s.r.o.Meta
Hosted endpointno (local only)no (local only)
Transports
AuthNoneOAuth or key
PricingFreePaid
x402nono
LicenceMITProprietary 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.
Read-only variant documentednoyes
llms.txtyesyes
Last release2026-09-232026-10-11
Terms last updatedno document linked
Privacy policy last updatedno document linkedcouldn'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
Popularity19k stars63k npm/wk

Verdicts

Agent Zero

Self-hosted under the MIT licence, with nine releases in the 90 days to 12 October 2026 and breaking changes listed in the release notes. The agent runs shell commands in its container with no approval step, the web interface has no login by default, and five CVEs from the past year have no published GitHub advisory.

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.

Before you call either

Agent Zero

  1. Set a UI login and password in Settings before publishing the port or opening a tunnel. The default has none
  2. Fill allowed_users, allowed_numbers or sender_whitelist before enabling a channel. An empty list accepts every sender
  3. Enable the Infection Check plugin when the agent reads mail, web pages or MCP results. It ships disabled
  4. Run v2.12 or later. It fixes a Telegram webhook authentication bypass and a WhatsApp media path traversal
  5. Call POST /api_message with the X-API-KEY header. The token changes when the UI login or password changes

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

Questions

Which is better for AI agents, Agent Zero or Muse Code?

Muse Code scores 61.3 (C) on agent readiness against Agent Zero's 54.2 (C), and leads in 4 of 7 scored categories. Agent Zero leads on reliability and payments & pricing.

Are Agent Zero and Muse Code open source?

Agent Zero is open source (MIT). No open-source release is listed for Muse Code.

Other comparisons with Agent Zero or Muse Code

Machine-readable

For companies

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