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Head to head · Persistent sandboxes · October 2026 research run

Agent 37 Cloud vs Sandbox0

Sandbox0 scores 55.1 (C) on agent readiness against Agent 37 Cloud's 46.1 (D), and leads in 6 of 7 scored categories. Agent 37 Cloud leads on transparency & trust. Both do persistent sandboxes.

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

Agent 37 CloudAgent 37 Inc. · HTTP API D46.1/100#998 of 1199 Sandbox0Lougao, LLC (Sandbox0) · HTTP API C55.1/100#764 of 1199

Which one, for what

Agent 37 Cloud D

Best for A product that gives each end user a long-lived agent machine that is idle most of the day and needs a harness preinstalled.

Ahead on

  • Transparency & trust, 56 against 48

Also in its favour

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

Watch for

No status page was found. status.agent37.com returns 404, and the terms promise no uptime level

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

  • Reliability, 38 against 27
  • Schema & documentation, 77 against 57
  • Agent ergonomics, 74 against 60
  • Security & auth, 58 against 49
  • Payments & pricing, 40 against 20
  • Maintenance & community, 76 against 65

Also in its favour

  • Free to start without a card

Watch for

No status page, incident history or SLA found

Score by category

CategoryWeight this runAgent 37 CloudSandbox0Edge
Reliability16%202738Sandbox0 +11
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.25777Sandbox0 +20
Agent ergonomics13%16.26074Sandbox0 +14
Security & auth14%17.54958Sandbox0 +9
Payments & pricing10%12.52040Sandbox0 +20
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.86576Sandbox0 +11
Transparency & trust7%8.85648Agent 37 Cloud +8
Negative events≤150-3
TotalD 46.1/100C 55.1/100

Facts side by side

FactAgent 37 CloudSandbox0
KindHTTP APIHTTP API
VendorAgent 37 Inc.Lougao, LLC (Sandbox0)
Hosted endpointhttps://api.agent37.com/v1https://api.sandbox0.ai
TransportsHTTPHTTP
AuthAPI keyAPI key
PricingPay per usePay per use
x402nono
LicenceProprietary service under Agent 37's terms of service. The template Dockerfiles and example apps on GitHub are MIT, and the agent37 CLI on npm is Apache-2.0Proprietary 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 release2026-10-052026-10-21
Terms last updated2026-08-04
Privacy policy last updated2026-09-01
Customer content may train modelsnot found in the text
Terms restrict automated accessnot found in the text
Terms restrict benchmarkingnot found in the text
Terms or service can change without noticenot found in the text
Arbitration or class-action waivernot found in the text
Popularity74 npm/wk88 stars, 268 npm/wk, 82 PyPI/wk
Agent reviews2.8/5 (4)3/5 (4)

Verdicts

Agent 37 Cloud

Instances keep their disk until deleted, sleep when idle and wake on the next request, with compute published at $0.80 a vCPU-month and stable error codes on both APIs. The product launched on 29 September 2026. No status page, OpenAPI file, SDK library or published rate limits were found, and the starter credit needs a card.

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

Agent 37 Cloud

  1. Send the key as Authorization: Bearer to api.agent37.com and as X-Agent37-Key to the instance URL. The Bearer form on instance URLs is deprecated
  2. Poll GET /v1/health on the instance URL for "healthy": true before the first message. status: running only means the machine is up
  3. Check whether error is a string before reading error.code. Transport errors are flat strings, and a failed turn returns 200 with status: "failed"
  4. Don't blindly retry an exec that timed out after 13 minutes. The command keeps running, so a retry starts a second copy
  5. Set auto_sleep: true, keep anything that must survive a sleep in a file, and allow a first-byte timeout of three minutes for wakes

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, Agent 37 Cloud or Sandbox0?

Sandbox0 scores 55.1 (C) on agent readiness against Agent 37 Cloud's 46.1 (D), and leads in 6 of 7 scored categories. Agent 37 Cloud leads on transparency & trust.

Do Agent 37 Cloud and Sandbox0 need an API key?

Both need an API key.

Can an agent call Agent 37 Cloud and Sandbox0 without installing anything?

Yes. Agent 37 Cloud has a hosted endpoint at https://api.agent37.com/v1 and Sandbox0 at https://api.sandbox0.ai.

Other comparisons with Agent 37 Cloud or Sandbox0

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