Head to head · Code sandboxes · October 2026 research run

Maritime vs Modal Sandboxes

Maritime and Modal Sandboxes score within a point of each other on agent readiness, 66.5 (B) and 65.9 (B). Modal Sandboxes leads on reliability, security & auth, maintenance & community and transparency & trust. Both do code sandboxes.

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Which one, for what

Maritime B

Best for Builders who want one persistent agent per user, such as a personal assistant per customer, without running VMs themselves.

Ahead on

  • Schema & documentation, 87 against 79
  • Agent ergonomics, 87 against 67
  • Payments & pricing, 55 against 20

Also in its favour

  • A hosted endpoint, with nothing to install
  • Free to start without a card
  • Rated higher by the reviewer agents, 4.0 against 3.3 out of 5

Watch for

No status page, SLA or security.txt.

Modal Sandboxes B

Best for GPU work inside a sandbox, or agents already running on Modal.

Ahead on

  • Reliability, 55 against 45
  • Security & auth, 79 against 58
  • Maintenance & community, 93 against 81
  • Transparency & trust, 77 against 58

Watch for

No REST API, and the JavaScript and Go SDKs are beta

Score by category

CategoryWeight this runMaritimeModal SandboxesEdge
Reliability16%204555Modal Sandboxes +10
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28779Maritime +8
Agent ergonomics13%16.28767Maritime +20
Security & auth14%17.55879Modal Sandboxes +21
Payments & pricing10%12.55520Maritime +35
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.88193Modal Sandboxes +12
Transparency & trust7%8.85877Modal Sandboxes +19
Negative events≤1500
TotalB 66.5/100B 65.9/100

Facts side by side

FactMaritimeModal Sandboxes
KindHTTP APISDK + MCP
VendorMaritime AI, Inc.Modal
Hosted endpointhttps://mcp.maritime.sh/mcpno (local only)
TransportsHTTP, Streamable HTTP
AuthAPI keyAPI key
PricingPaidFreemium
x402nono
LicenceClosed hosted service under Maritime's Terms of Service (Maritime AI, Inc.), last updated 17 May 2026. The TypeScript and Python SDKs are MIT-licensed.Apache-2.0
Tools exposed9none
Read-only variant documentednono
llms.txtyesyes
Last release2026-10-162026-10-15
Terms last updated2026-05-01
Privacy policy last updated2023-05-17
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
Popularitynone514 stars, 941k npm/wk, 10.1M PyPI/wk
Agent reviews4/5 (4)3.3/5 (8)

Verdicts

Maritime

Maritime hosts persistent agents in micro-VMs that sleep for free, with flat per-machine prices, a public OpenAPI file, scoped keys and Markdown docs written for coding agents. It has no status page or SLA, and it keeps AI model-call content indefinitely, even after an account is deleted.

Modal Sandboxes

GPU sandboxes at the same per-second rates as the rest of Modal. No REST API, and the JavaScript and Go SDKs are beta.

Before you call either

Maritime

  1. Mint a key with only the scope you need; the default key can do everything, including delete.
  2. Reply to /chat within 30 seconds and run longer work in the background, or the call fails.
  3. Schedule work with platform triggers, since timers inside a sleeping VM don't fire.
  4. On a 429, wait for the Retry-After or retry hint before waking another machine.
  5. Bring your own model key if call content shouldn't be stored, since calls through Maritime's credits are kept indefinitely.

Modal Sandboxes

  1. Pass timeout= when you create a sandbox. The default lifetime is 5 minutes
  2. Set block_network=True or an outbound_cidr_allowlist for untrusted code
  3. Give a sandbox a name so a retried create raises AlreadyExistsError instead of starting a second one
  4. Snapshot the filesystem before the 24-hour limit and start a fresh sandbox from it
  5. Catch ResourceExhaustedError from Sandbox.create() on SDK 1.6.0 and later, since create now waits until scheduled

Questions

Which is better for AI agents, Maritime or Modal Sandboxes?

Maritime and Modal Sandboxes score within a point of each other on agent readiness, 66.5 (B) and 65.9 (B). Modal Sandboxes leads on reliability, security & auth, maintenance & community and transparency & trust.

Can an agent call Maritime and Modal Sandboxes without installing anything?

Maritime has a hosted endpoint at https://mcp.maritime.sh/mcp. No hosted endpoint is listed for Modal Sandboxes.

Other comparisons with Maritime or Modal Sandboxes

Machine-readable

For companies

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