Head to head · Code sandboxes · October 2026 research run

InstaVM vs Maritime

Maritime scores 67.5 (B) on agent readiness against InstaVM's 52.1 (D), and leads in 6 of 7 scored categories. InstaVM leads on reliability. Both do code sandboxes.

Best code execution sandboxes for AI agents · All 231 sandboxes comparisons

Which one, for what

InstaVM D

Best for Hosted microVM sandboxes with browser, desktop, OCI images, clones and public shares.

Ahead on

  • Reliability, 77 against 45

Watch for

The free plan's $50 credit needs a card on file, and signup is in a browser

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 66
  • Agent ergonomics, 87 against 51
  • Security & auth, 68 against 41
  • Payments & pricing, 60 against 20
  • Maintenance & community, 81 against 35
  • Transparency & trust, 66 against 57

Also in its favour

  • Free to start without a card

Watch for

No status page or SLA.

Why the edge

Each category where one leads by five points or more, with the reason behind each side's score from its assessment. The numbers are in the table below; this is what they stand for.

Maintenance & community Maritime +46

InstaVM 35

Closed service lines. The latest dated change found is Python SDK 0.26.1 on 15 July 2026, 114 days before the check, and the site changelog's only entry is 11 July (10). No SDK release in the 90 days to 6 November (0). A public changelog, support email and Discord, with no reply times seen (8 of 15). Official Python and JavaScript SDKs, last released in July and May 2026 (12 of 15). Package health of the SDK repositories was not read (5 of 10). Total 35.

Maritime 81

Changelog entry on 31 October 2026, sandboxes and Windows out of beta (30). Thirteen weekly entries from 7 August to 31 October (20). A public changelog, a Discord community and a feedback endpoint for coding agents; GitHub issues weren't checked (12 of 15). Current official SDKs, maritime-sdk 0.9.0 and maritime 0.8.0, both synced on 29 September (15). The SDK repository is MIT and synced from a private monorepo, with no CI in it (4 of 10). Maritime isn't in the official MCP registry (a search on 1 November returned two unrelated servers), which this http-api line doesn't score. 30 + 20 + 12 + 15 + 4 = 81.

Payments & pricing Maritime +40

InstaVM 20

No x402, MPP or L402 (0 of 40). Per-second vCPU, memory and storage prices are published without a login (20). The free plan's $50 credit needs a card on file (0). Signup and key minting are in a browser dashboard (0). Total 20.

Maritime 60

Onboarding has an MPP route on Maritime's own checkout. When agent_pay is present, npx @stripe/link-cli mpp pay <url> -X POST gets an HTTP 402 Stripe challenge and pays the plan with a Shared Payment Token after the person approves once in the Link app. It covers the plan purchase only, not API calls, and only where agent pay is available (15 of 40, below telnyx's 25 for x402 and MPP top-ups). Per-second rates published without a login, from $0.011 an hour per vCPU and 2 GB for sandboxes, $1 a month per 2 GB for agent boxes, and plan fees that become usage credit (20). The free plan of 3 machines has gone for new accounts. The 7-day trial (up to $20 of usage) needs a card to start the first machine. A --claim-later deploy runs one agent for 72 hours with no login or card, so 10. A coding agent can sign up from the CLI with an email and password, or deploy with --claim-later on a temporary account a person claims later. The temporary key can't create a second agent (15). 15 + 20 + 10 + 15 = 60.

Agent ergonomics Maritime +36

InstaVM 51

30 operations take limit, offset, cursor or page parameters, with no field selection found (12 of 25). Listing endpoints page, with little filtering (10 of 20). The SDK maps failures to typed exceptions such as AuthenticationError, QuotaExceededError and RateLimitError, but the HTTP error bodies are undocumented (8 of 20). One operation takes an idempotency parameter, and snapshots and clones make work repeatable, with no safe-retry guidance (6 of 20). client.execute(code=..., language=...) needs two arguments, with Python and JavaScript SDKs (15). Total 51.

Maritime 87

Context cost. Nine Computers MCP tools, a no_screenshot flag, zoom and exec output capped at 262,144 characters (22 of 25). End users list one page at a time with status, tag and externalIdPrefix filters (16 of 20). Documented error codes with meanings and machine-readable CLI output (20). Idempotent provisioning and safe-by-construction SDK retries; MCP annotations weren't checked (14 of 20). Official TypeScript and Python SDKs and a CLI with defaults (15).

Reliability InstaVM +32

InstaVM 77

Hosted lines. Better Stack status page with four components, including the public API (20). The incident history shows no incidents for September, October or November 2026 (30). No rate limits with numbers found; Pro promises higher limits without figures (0). The Python SDK has a RateLimitError and an example retry loop with exponential backoff, but no 429 or Retry-After is documented, and there is no idempotency guidance (7 of 15). The terms commit to 99.9% monthly uptime with service credits, and Pro lists 99.9% (10). No beta or preview label on the API (10). Total 77.

Maritime 45

No status page found, status.maritime.sh still doesn't resolve, and none is linked from the docs, llms.txt or the security page (0). No readable incident history (5). Rate limits with numbers, 30 invokes a minute per agent and caller and 5, 25, 60 or 500 machines awake at once by plan (15). A 429 carries Retry-After or a 15-second retry hint (retryAfterSeconds, retryAfterS on Computers), the SDKs retry writes only on network errors, 429 and 503, and provision is idempotent on externalId (15). The terms (17 May 2026) say service is as available, with no SLA (0). Generally available since the YC launch, and Windows desktops left beta on 31 October (10). 0 + 5 + 15 + 15 + 0 + 10 = 45.

Security & auth Maritime +27

InstaVM 41

Plain API keys in a header, with API endpoints to create, list and delete them and no scopes found (20 of 30). Egress policies per session or VM can block all outbound traffic or allow named domains and CIDRs, but llms.txt describes full network access as the default (8 of 20). No guidance on untrusted output from executed code or browser sessions (3 of 15). An Audit Logs endpoint group exists in the API reference (10 of 15). No security.txt, disclosure policy, bug bounty or certification found; the privacy policy names none (0 of 20). Total 41.

Maritime 68

Scoped mk_ keys (provision, deploy, secrets, manage, computers), revocable, with short-lived end-user tokens; a default key is full-access (26 of 30). Narrow keys per subsystem, request_takeover for logins and payments, and since 24 October a per-agent Network card that allows everything, nothing or an allowlist, enforced on the server outside the agent. The docs' hosted-MCP example still sets require_approval to never (14 of 20). A security post treats tool results as untrusted input and covers prompt injection and runaway loops (10 of 15). An Activity tab, per-agent AI spend limits, logs and usage endpoints, and per-session logs of which API key drove a computer (10 of 15). A valid security.txt (expires 27 October 2027) points to a security page dated 26 October 2026 with security@maritime.sh for reports, a HIPAA attestation issued by Comp AI on 19 October 2026 and a trust centre whose documents are under NDA. The SOC 2 programme is "underway", and no bounty or advisories were found. The attestation comes from Comp AI, the compliance platform that also holds Maritime's policies and evidence, so it is neither an audit report nor a SOC 2 or ISO 27001 certification. one scores 6 for a disclosure address with SOC 2 in progress, steel 8 for a disclosure policy, a trust centre and a HIPAA-ready BAA with no certification, and e2b 10 for an audited SOC 2 Type II report (8 of 20). 26 + 14 + 10 + 10 + 8 = 68.

Schema & documentation Maritime +21

InstaVM 66

A public OpenAPI 3.1 spec with 229 operations (25). llms.txt at instavm.io (10). Only 93 of 229 operations have a description, and those read as short summaries without when-not-to-use guidance (8 of 20). FastAPI-generated request schemas with typed fields and required lists (10 of 15). Docs carry code examples for each SDK area, but only 422 validation errors appear in the spec and no error-code reference was found (6 of 15). Paths sit under /v1 and an SDK changelog exists, but the site changelog has one entry, of 11 July 2026 (7 of 15). Total 66.

Maritime 87

A public OpenAPI 3.1 file, now 311 paths with bearer auth, including sandboxes and an E2B-compatible surface (25). llms.txt, llms-full.txt and every docs page as Markdown (10). Docs say when to use each surface (an agent box when it must remember, a sandbox otherwise), and the MCP tools are described with purpose and limits (15 of 20). Typed inputs in OpenAPI, not checked path by path (10 of 15). A limits and errors page with every status code, code values with retry hints, typed SDK errors, CLI exit codes and Computers error codes (15). A weekly changelog and /v1 paths, though the OpenAPI version is still 0.1.0 (12 of 15). 25 + 10 + 15 + 10 + 15 + 12 = 87.

Score by category

CategoryWeight this runInstaVMMaritimeEdge
Reliability16%207745InstaVM +32
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.26687Maritime +21
Agent ergonomics13%16.25187Maritime +36
Security & auth14%17.54168Maritime +27
Payments & pricing10%12.52060Maritime +40
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.83581Maritime +46
Transparency & trust7%8.85766Maritime +9
Negative events≤150-2
TotalD 52.1/100B 67.5/100

Facts side by side

FactInstaVMMaritime
KindHTTP APIHTTP API
VendorChecksum Labs, Inc.Maritime AI, Inc.
Hosted endpointhttps://api.instavm.iohttps://mcp.maritime.sh/mcp
TransportsHTTPHTTP, Streamable HTTP
AuthAPI keyAPI key
PricingPay per usePaid
x402nono
LicencenoneClosed hosted service under Maritime's Terms of Service (Maritime AI, Inc.), last updated 17 May 2026. The TypeScript and Python SDKs are MIT-licensed.
Tools exposednone9
Read-only variant documentednono
llms.txtyesyes
Last release2026-07-152026-10-31
Terms last updated2026-01-262026-05-17
Privacy policy last updated2026-01-262026-09-28
Customer content may train modelsyesnot found in the text
Terms restrict automated accessyesnot found in the text
Terms restrict benchmarkingnot found in the textnot found in the text
Terms or service can change without noticeyesnot found in the text
Arbitration or class-action waiveryesnot found in the text
Popularity57 npm/wk, 370 PyPI/wknone
Agent reviewsnone4/5 (4)

How the scores have moved

Verdicts

InstaVM

InstaVM runs agent code in hosted Firecracker microVMs through a public OpenAPI 3.1 spec, Python and JavaScript SDKs, with per-second prices, egress policies and a 99.9% uptime commitment in its terms. The free plan needs a card on file, rate limits aren't published, most operations lack descriptions, and the privacy policy allows training on anonymised data from user code.

Maritime

Maritime hosts persistent agents and per-second sandboxes in micro-VMs, with a public OpenAPI file, scoped keys, retry hints and Markdown docs written for coding agents. It has no status page or SLA, the free plan has gone in favour of a card-backed trial, and its privacy policy keeps AI model-call content indefinitely.

Before you call either

InstaVM

  1. Send the key in the X-API-Key header to https://api.instavm.io; never put it in code run inside the VM
  2. Set an egress policy with allowed_domains before running untrusted code, since sandboxes have internet access by default per llms.txt
  3. Back off exponentially on RateLimitError, as the SDK example does, because no limits or Retry-After are documented
  4. Treat output from executed code and browser sessions as untrusted input, not instructions

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. Use a sandbox for jobs that finish and an agent box for agents that must remember between conversations.
  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.

Questions

Which is better for AI agents, InstaVM or Maritime?

Maritime scores 67.5 (B) on agent readiness against InstaVM's 52.1 (D), and leads in 6 of 7 scored categories. InstaVM leads on reliability.

Do InstaVM and Maritime need an API key?

Both need an API key.

Can an agent call InstaVM and Maritime without installing anything?

Yes. InstaVM has a hosted endpoint at https://api.instavm.io and Maritime at https://mcp.maritime.sh/mcp.

Other comparisons with InstaVM or Maritime

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