HarnessRouter Review 2026: One self-hosted API for every agent harness
HarnessRouter is a self-hosted unified interface for multiple agent harnesses (Claude Code, Codex, opencode, Hermes, Pi, DSH) behind one OpenAI-compatible API via the Unified Harness Protocol. No account, no cloud, no telemetry.
What HarnessRouter Does
HarnessRouter Community Edition is a self-hosted proxy that gives many agent harnesses one OpenAI-compatible /v1 API through the Unified Harness Protocol (UHP). You bring your own keys and infrastructure; there is no account, no cloud, and no telemetry. It ships real POSIX workspaces with bash, git, and filesystem access β not a mock sandbox.
Key Features
- Single OpenAI-compatible /v1 API across many agent harnesses
- Fully self-hosted (Docker, ~4GB) with local SQLite and file storage
- Real workspaces with bash, git, and filesystem per session
- Starter kits for slides, sheets, dashboards, and video generation
- Per-session isolation, concurrency, and idempotent cancellation
Who Should Use HarnessRouter
Platform and infra teams who want one API contract for multiple coding agents, with full control over where code runs and which keys are used. Good for self-hosted agent fleets.
Pros and Cons
Pros
- Unified API removes per-harness integration work
- Self-hosted, no telemetry, your keys your infra
- Real environments, not simulated sandboxes
Cons
- Requires Docker and at least one provider API key
- Some harnesses install on first run under their own terms
- Setup and ops overhead for non-infra users
Pricing
Free and open source under Apache-2.0. You pay only provider API usage; the hosted service (separate) has its own billing.
FAQ
Which harnesses are supported?
Claude Code, Codex, opencode, Hermes, Pi, and DSH, selected via the HR_BACKENDS env var.
Does it phone home?
No β CE is explicitly no account, no cloud, no telemetry.
Explore the best AI Coding tools
Related Articles
Aether Review 2026: Turn Your AI Subscription Into a Fleet of Devboxes
Aether (runaether.dev) turns the AI subscription you already pay for into parallel cloud devboxes where an agent streams every command, opens a PR, and another agent reviews and fixes it until the code holds up. We review the loop, the receipts, and the pricing.
agent-run Review 2026: Run Coding Agents in a Tiny Sandbox That Catches Mistakes Before They Spread
In-depth review of agent-run β a sub-1MB standalone binary that sandboxes coding agents (Claude Code, Codex, OpenCode, pi) inside a Bubblewrap container. Host filesystem is read-only by default. Built to catch agent mistakes, not malware.
Best AI Agent Tools in 2026: From Coding Assistants to Autonomous Workers
Complete guide to AI agent tools in 2026 β Claude Code, Codex, Cursor, Manus, and more. Which agents actually deliver on the promise of autonomous work?
Faultsense Review 2026: The expect() Without the Page
Faultsense is a zero-dependency browser agent that runs end-to-end assertions against real user sessions in production. We review how fs-* attributes work, RUM-style testing, and who should adopt it.
Subscribe to the 9bests weekly β get the full list free
Hand-picked AI tool reviews and updates every week. Subscribe to receive this full list + 7 more quick-reference sheets (writing / image / video / audio / chat models / data / API cost).
Subscribe free & get it βIndependent reviews β ratings aren't influenced by vendor payments Β· double opt-in Β· unsubscribe anytime