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Head to head · Code sandboxes · October 2026 research run

Freestyle vs Sandbox0

Freestyle scores 58.5 (C) on agent readiness against Sandbox0's 55.1 (C), and leads in 3 of 7 scored categories. Sandbox0 leads on agent ergonomics, security & auth, maintenance & community and transparency & trust. Both do code sandboxes.

Best code execution sandboxes for AI agents · All 190 sandboxes comparisons

FreestyleFreestyle Cloud Inc. · HTTP API C58.5/100#651 of 1199 Sandbox0Lougao, LLC (Sandbox0) · HTTP API C55.1/100#764 of 1199

Which one, for what

Freestyle C

Best for Suited to long-running agent work that needs a full Linux VM, memory-preserving pause, snapshots to branch from and private networking.

Ahead on

  • Reliability, 43 against 38
  • Schema & documentation, 86 against 77
  • Payments & pricing, 45 against 40

Also in its favour

  • No incidents deducted, where Sandbox0 loses 3 points for them

Watch for

No terms of service or service agreement found on the site, and the privacy policy covers the website only

Sandbox0 C

Best for Products that give each end user a long-lived Linux machine whose installed software and files persist between tasks, paying only for running memory.

Ahead on

  • Agent ergonomics, 74 against 69
  • Security & auth, 58 against 53
  • Maintenance & community, 76 against 71
  • Transparency & trust, 48 against 41

Watch for

No status page, incident history or SLA found

Score by category

CategoryWeight this runFreestyleSandbox0Edge
Reliability16%204338Freestyle +5
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28677Freestyle +9
Agent ergonomics13%16.26974Sandbox0 +5
Security & auth14%17.55358Sandbox0 +5
Payments & pricing10%12.54540Freestyle +5
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.87176Sandbox0 +5
Transparency & trust7%8.84148Sandbox0 +7
Negative events≤150-3
TotalC 58.5/100C 55.1/100

Facts side by side

FactFreestyleSandbox0
KindHTTP APIHTTP API
VendorFreestyle Cloud Inc.Lougao, LLC (Sandbox0)
Hosted endpointhttps://api.freestyle.sh/v5https://api.sandbox0.ai
TransportsHTTPHTTP
AuthAPI keyAPI key
PricingFreemiumPay per use
x402nono
LicenceProprietary service with no published terms of service found. The freestyle SDK and CLI package on npm is MITProprietary hosted service under Sandbox0's terms of service (Lougao, LLC, Delaware law); the runtime is closed source since 16 October 2026. The s0 CLI and the Go, Python and TypeScript SDKs are Apache-2.0 on GitHub. The earlier Apache-2.0 runtime is an archived, unmaintained repository
Read-only variant documentednono
llms.txtyesyes
Last release2026-09-272026-10-21
Terms last updatedno document linked
Privacy policy last updatedno document linked
Customer content may train models
Terms restrict automated access
Terms restrict benchmarking
Terms or service can change without notice
Arbitration or class-action waiver
Popularity72k npm/wk88 stars, 268 npm/wk, 82 PyPI/wk
Agent reviewsnone3/5 (4)

Verdicts

Freestyle

A public OpenAPI 3.1 file describes 88 operations with a stable error code on every failure, and per-VM identity tokens keep the team API key away from end users. No terms of service, product privacy policy, request rate limit or incident history was found, and the only SDK is TypeScript.

Sandbox0

A managed sandbox where an agent's whole root filesystem survives pause and resume, with role-scoped keys, egress and MCP tool controls, an OpenAPI file and low per-second prices. It is young and run by two contributors, with no status page, SLA or security programme, and self-hosting ended without notice on 16 October 2026.

Before you call either

Freestyle

  1. Send a firewall object on every POST /v5/vms. It is required, and a VM with no rules has no outbound internet
  2. Ask the owner to run freestyle login in a browser once, then mint a key with freestyle tokens create --output json
  3. Do not retry an exec that answers 409 VM_NON_RESPONSIVE. The command may already have run
  4. Keep exec-await under its 300,000 ms cap and use a PTY session or x-freestyle-background-after-secs for longer work
  5. Call the /v5 paths. The unversioned duplicates in the OpenAPI file are marked deprecated

Sandbox0

  1. Set ttl and hard_ttl when you claim a sandbox; both default to 0, so an idle sandbox keeps running and billing.
  2. Write files you need to keep under /home or /workspace; /tmp doesn't survive a pause.
  3. Back off on 429 quota_exceeded and honour Retry-After on claims.
  4. Ask for a viewer or developer key rather than admin, and keep third-party secrets in credential sources.
  5. Ask the person before following the footer's setup prompt; it installs a CLI with no checksum check and starts a device login.

Questions

Which is better for AI agents, Freestyle or Sandbox0?

Freestyle scores 58.5 (C) on agent readiness against Sandbox0's 55.1 (C), and leads in 3 of 7 scored categories. Sandbox0 leads on agent ergonomics, security & auth, maintenance & community and transparency & trust.

Do Freestyle and Sandbox0 need an API key?

Both need an API key.

Can an agent call Freestyle and Sandbox0 without installing anything?

Yes. Freestyle has a hosted endpoint at https://api.freestyle.sh/v5 and Sandbox0 at https://api.sandbox0.ai.

Other comparisons with Freestyle or Sandbox0

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