Head to head · Persistent sandboxes · October 2026 research run

Agent 37 Cloud vs SPACE

SPACE scores 56.2 (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 maintenance & community. Both do persistent sandboxes.

Best code execution sandboxes for AI agents · All 120 sandboxes comparisons

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

  • Maintenance & community, 65 against 26

Also in its favour

  • A hosted endpoint, with nothing to install

Watch for

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

SPACE C

Best for Teams that want E2B-style microVM sandboxes on their own Linux and Kubernetes hosts, with egress and credential control outside the guest.

Ahead on

  • Reliability, 32 against 27
  • Schema & documentation, 75 against 57
  • Agent ergonomics, 66 against 60
  • Security & auth, 64 against 49
  • Payments & pricing, 60 against 20
  • Transparency & trust, 68 against 56

Also in its favour

  • Free to start without a card
  • Open source

Watch for

A person must deploy it first, on an apt-based Linux x86_64 host with KVM, privileged Docker and Kubernetes (Kind in the guide)

Score by category

CategoryWeight this runAgent 37 CloudSPACEEdge
Reliability16%202732SPACE +5
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.25775SPACE +18
Agent ergonomics13%16.26066SPACE +6
Security & auth14%17.54964SPACE +15
Payments & pricing10%12.52060SPACE +40
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.86526Agent 37 Cloud +39
Transparency & trust7%8.85668SPACE +12
Negative events≤1500
TotalD 46.1/100C 56.2/100

Facts side by side

FactAgent 37 CloudSPACE
KindHTTP APIHTTP API
VendorAgent 37 Inc.Perplexity
Hosted endpointhttps://api.agent37.com/v1no (local only)
TransportsHTTPHTTP
AuthAPI keyOAuth or key
PricingPay per useFree
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-2.0Apache-2.0
Read-only variant documentednono
llms.txtyesno
Last release2026-10-05none
Terms last updated2026-08-04no document linked
Privacy policy last updated2026-09-01no document linked
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/wknone
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.

SPACE

Once deployed, SPACE's native API has a public OpenAPI 3.1 contract, stable error codes with a retryable flag and 24-hour idempotency keys, and egress and credential controls sit outside the VM. A person must first deploy it on a Linux x86_64 host with KVM and Kubernetes. Version 0.8.0 has no tagged release, changelog or public container images.

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

SPACE

  1. Ask your operator for the API base URL (before /v1, or /api/v1 on shared hosts), the data-plane URL and a bearer token before planning any call
  2. Poll the returned operation until it succeeds and the sandbox is running before creating a command. A 202 response is not readiness
  3. Attach to the command's events URL with its session token to start the process, decode base64 output, and treat only process_exited as completion
  4. Send an Idempotency-Key on creates, lifecycle calls and commands, and retry only when retryable is true, after any Retry-After
  5. Save output as it arrives. Reconnecting with Last-Event-ID returns resync_required, not the missed output

Questions

Which is better for AI agents, Agent 37 Cloud or SPACE?

SPACE scores 56.2 (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 maintenance & community.

Do Agent 37 Cloud and SPACE need an API key?

Agent 37 Cloud needs an API key. SPACE takes an API key or an OAuth sign-in.

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

Agent 37 Cloud has a hosted endpoint at https://api.agent37.com/v1. No hosted endpoint is listed for SPACE.

Are Agent 37 Cloud and SPACE open source?

No open-source release is listed for Agent 37 Cloud. SPACE is open source (Apache-2.0).

Other comparisons with Agent 37 Cloud or SPACE

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