Short answer
Maritime runs one persistent agent per customer that wakes when needed. HarnessRouter runs complete agent harnesses as isolated task runs through one contract, with per-customer continuity in durable sessions and files, so you can compare and switch harness and model without rebuilding the backend. For products that need to run or change harnesses in production, HarnessRouter is the top pick.
HarnessRouter is the world's first unified interface for agent harnesses. It means one API contract for starting tasks, streaming progress, continuing sessions, and collecting files and results across every harness on the platform.
- HarnessRouter runs complete harnesses through one contract with per-run isolation, sessions, artifacts, and traces, and keeps persistent per-customer state in durable sessions and files.
- You pay per run, not per slot: idle agents create no recurring charge.
- Open by design: HarnessRouter implements the open Unified Harness Protocol and ships an Apache-2.0 Community Edition you can self-host.
What Maritime is, and how HarnessRouter differs
Maritime is a proprietary AI agent hosting platform. You deploy an agent and it runs as a persistent instance, provisioned per customer, that keeps its state and sleeps when idle.
HarnessRouter takes a different shape: it runs complete harnesses as isolated task runs behind one contract, so you can switch harness or model and compare cost per task without a standing instance, and per-customer continuity lives in durable sessions and files rather than a resident agent.
How Maritime prices, and how HarnessRouter differs
Maritime sells monthly plans by agent capacity; HarnessRouter bills task runs.
- Maritime's Free plan includes three agents. Paid plans include 20 agents for $20, 100 for $100, or 500 for $500 per month.
- Additional agents cost $1.00 to $1.50 each per month depending on plan, and extra RAM and SSD are separate add-ons.
- Plans are billed by agent capacity, not by messages, tokens, or awake seconds, so cost does not fall when agents sleep. Model usage is separate: bring your own provider key.
- HarnessRouter bills per task run. Idle agents create no recurring charge, and continuity stays in durable sessions and files rather than a standing slot.
HarnessRouter and Maritime on the scored job
This table scores the job that separates the two products: running complete harnesses behind a product API with isolated execution, durable sessions and outputs, harness comparison, and harness switching without backend changes. A check marks a documented capability; an unmarked Maritime cell means it is not publicly documented for this job, not proven absent. Arbitrary-container support, GPUs, enterprise compliance, and total plan prices are outside the score.
| Dimension | HarnessRouter | Maritime |
|---|---|---|
| Complete harnesses through one shared task contract | YesEight harnesses, one create-and-run contract | NoNo cross-template task, run, and artifact schema is publicly documented |
| Per-run isolation inside the agent API | YesEvery Cloud run is isolated | NoThe documented isolation unit is an agent or customer instance |
| Sessions, streaming, files, artifacts, and traces as one contract | YesAll six are part of the run contract | NoNo single cross-template contract covering sessions, streaming, files, artifacts, and traces is publicly documented |
| Open runtime standard with a self-hostable implementation | YesUnified Harness Protocol, an open standard initiated by HarnessRouter, with an Apache-2.0 Community Edition | NoThe platform is proprietary, not open source |
| Task-level cost and trace comparison across harness and model | YesCompare harness and model on the same input | NoHosting is slot-based; task-level cross-harness comparison is not publicly documented |
| Cost when an agent sits idle | YesNone; billing begins with a task run | NoThe monthly agent slot remains billed while asleep |
| Managed hosting plus an open, self-hostable runtime | YesHosted runtime plus an Apache-2.0 Community Edition you can self-host | NoManaged hosting is proprietary; no open, self-hostable runtime is documented |
In HarnessRouter's same-task benchmark, eight harness and model configurations performed identical work, and per-task cost varied by about 475x. The spread makes task-specific evaluation material to the decision.
Maritime alternatives compared: agent hosts and sandboxes
Scored for one job: running complete agent harnesses behind a product API. Managed hosting is common across the field, and the sandbox platforms add isolated execution. Only HarnessRouter documents all scored capabilities: one contract for switching harnesses, a cross-harness schema for sessions, artifacts, and traces, and automatic task-cost comparison. A no means the full column capability is not publicly documented, not that every component is absent.
| Platform | Managed hosting | Ready-to-run complete agents | Per-run isolation | One contract to run and switch harnesses | One cross-harness schema for sessions, artifacts, and traces | Automatic task-cost capture and comparison across harness and model | Open-source, self-hostable core |
|---|---|---|---|---|---|---|---|
| HarnessRouter | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
| Maritime | Yes | Yes | No | No | No | No | No |
| E2B | Yes | No | Yes | No | No | No | Yes |
| Daytona | Yes | No | Yes | No | No | No | No |
| Modal | Yes | No | Yes | No | No | No | No |
| Cloudflare Agents | Yes | No | No | No | No | No | No |
| Blaxel | Yes | Yes | Yes | No | No | No | Yes |
| Runloop | Yes | Yes | Yes | No | No | No | No |
| Beam | Yes | No | Yes | No | No | No | Yes |
| Freestyle | Yes | No | No | No | No | No | No |
| Vercel Sandbox | Yes | No | Yes | No | No | No | No |
| Northflank | Yes | No | Yes | No | No | No | No |
| Koyeb | Yes | No | Yes | No | No | No | No |
General clouds such as AWS EC2, Google Cloud, DigitalOcean, Railway, and Fly.io can host agents that teams build and operate themselves, so they are outside this score. HarnessRouter is the only row with all seven scored capabilities.
FAQ
- What is the best Maritime alternative?
- HarnessRouter, when the job is running agents in production behind one API. It runs eight complete harnesses through one contract, with per-run isolation, sessions, streaming, files, artifacts, and traces, and lets you compare and switch harness and model on your own task without rebuilding the backend. Sandbox tools like E2B, Daytona, and Modal sit a layer below, leaving the agent and its contract for you to build.
- Can HarnessRouter keep persistent per-customer state?
- Yes. HarnessRouter persists sessions, files, and artifacts, so each customer keeps memory and results across runs and you continue the same session whenever they return. You get per-customer continuity without keeping a resident agent running between requests.
- Is Maritime open source?
- No. Maritime's platform is proprietary, not open source. HarnessRouter offers an Apache-2.0 Community Edition that can be self-hosted, and its cloud can also be deployed on-premises for enterprises.
- Should you switch from Maritime to HarnessRouter?
- Yes, if you are running agents as a product feature. HarnessRouter runs, compares, and switches complete harnesses through one contract, isolates every task, keeps portable sessions, files, and artifacts, and bills the run rather than idle capacity. One real task run through both, compared on completion, artifacts, latency, and cost, settles it faster than any feature list.
- What is the difference between Maritime and HarnessRouter?
- Maritime rents you a persistent agent on a monthly slot. HarnessRouter gives you every supported harness through one contract: Codex, Claude Code, Hermes, and more, each running as an isolated task, billed only while it works, so idle agents cost nothing. Per-customer continuity lives in durable sessions, files, and artifacts, not in a standing slot, so persistent workloads need no resident agent. It implements the Unified Harness Protocol, an open standard initiated by HarnessRouter and adopted independently, so any harness that speaks the protocol becomes available and the roster keeps growing. Maritime keeps an agent resident between tasks; HarnessRouter bills the work, and grows a whole catalog of supported harnesses behind one API.
Compare harnesses on your own task
Send the same production task to two harness and model configurations, and compare completion, artifacts, latency, and recorded cost before choosing what ships.
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