Overview
HarnessRouter and layahost are both API-first products, but they solve very different problems. HarnessRouter is an agent runtime that lets you plug leading AI harnesses (Codex, Claude Code, Hermes, DeepSeek Harness, and more) into your product as a backend. It handles the entire execution lifecycle—sandboxes, orchestration, retries, cost controls—so you can focus on your product. layahost, by contrast, is a hosted API for typed decisions. You send a piece of text and a question with a fixed set of answers, and you get back the chosen answer with a probability for every option, as JSON your code can branch on.
In short: HarnessRouter runs agents that produce work (code, files, videos, games). layahost makes decisions about text (moderation, routing, intent, scoring).
Feature Comparison
| Feature | HarnessRouter | layahost |
|---|---|---|
| Primary Purpose | Run full AI agent harnesses as a backend | Hosted API for typed decisions on text |
| Core Output | Finished work: code, files, videos, games, artifacts, traces | Chosen answer from a fixed set, with probabilities, as JSON |
| Interface / Protocol | Unified Harness Protocol (UHP), open standard | Jev System One API wire format (/v1/systemone, /v1/decide) |
| Model / Harness Choice | Multiple harnesses (Codex, Claude Code, Hermes, Pi, DeepSeek Harness) and models (gpt-5.x, claude-opus-4.8) | Single open Laya model; custom fine-tuned checkpoints available |
| Deployment Options | Cloud (hosted) or Community Edition (self-hosted, Apache 2.0) | Hosted only, EU servers (Helsinki, Finland) |
| Sandboxing / Isolation | One isolated sandbox per task, scales on demand | Not applicable; text processed in memory |
| SDK Compatibility | HarnessRouter API or UHP contract; starter kits provided | Official Jev SDKs (Python, JavaScript) work after changing base URL and key |
| Customization | Route between harness × model combinations; benchmark quality, latency, cost | Fine-tune a private Laya checkpoint on your labelled examples |
| Data Handling | Cloud: HarnessRouter operates runtime; Community Edition: your keys, state, files stay in your environment | EU servers, in-memory processing, never used for training; logs keep verdicts 7 days |
| Rate Limits | Not specified in provided content | 600 requests/min per key; up to 32 questions per request; 32,000 characters |
| Image Support | Can produce videos and games (multimodal output) | Text only; no image input |
| Free Tier | Start at $0, no card needed; waiting is free | No free tier; prepaid from $10; demo free to try |
Pricing
HarnessRouter
HarnessRouter offers a generous free start: $0, no card needed, to explore the console and configure agents. Usage is drawn only while hosted tasks run; waiting is free. You have two billing paths:
- Use a HarnessRouter key: Every model at its listed catalog price, no markup. Plans from $20/month include their full price as usage.
- Bring your own API keys: Your provider bills your model usage directly. You pay for Agent work only; waiting is free.
Community Edition is free and open source (Apache 2.0) for self-hosting on your own infrastructure.
layahost
layahost uses flat, prepaid pricing: $5 per million decisions. Credit starts at $10 (which buys 2M decisions) and never expires while your account is active. Volume discounts: +10% credit from $100, +20% from $500. Rejected and failed requests (4xx, 5xx) are free. Invoices with VAT ID are available. There is no subscription or per-seat fee.
Pros and Cons
HarnessRouter
Pros:
- One API to access multiple leading agent harnesses and models
- Removes months of backend engineering (sandboxes, orchestration, retries, cost controls)
- Open source Community Edition for self-hosting with full control
- Serverless runtime scales without infrastructure work
- Transparent pricing with no model markup and free waiting time
Cons:
- More complex integration than a simple decision API
- Requires understanding of harnesses, models, and UHP concepts
- Cloud pricing can scale with usage; cost depends on harness × model choice
layahost
Pros:
- Extremely simple: send text and a question, get a typed answer with probabilities
- Flat, predictable pricing at $5 per million decisions
- Jev-compatible API allows easy migration with official SDKs
- EU-hosted with strong privacy (in-memory, no training use)
- Custom fine-tuning available for domain-specific labels
Cons:
- Limited to text-based decisions; no image support
- Single model (Laya) may be less accurate than Jev on some benchmarks
- No free tier; requires prepaid credit from $10
- Not suitable for generating code, files, or complex agent workflows
Verdict
HarnessRouter and layahost serve fundamentally different needs. HarnessRouter is a full agent runtime for building products that generate code, files, videos, or games, offering multiple harnesses and models through one API. layahost is a lightweight, flat-priced decision API for moderation, routing, intent, and scoring on text. Choose HarnessRouter if you need autonomous agents that produce work; choose layahost if you need fast, cheap, typed decisions on text.