HarnessRouter open-sources a unified API to run Codex, Claude Code and more as agent backends
daniel_mac8 · x · 2026-09-20
HarnessRouter is a new open-source project with a simple pitch: routing not for models, but for agent harnesses. It turns existing harnesses like Codex, Claude Code, Hermes, PI and DSH into plug-and-play agent backends.
Key points:
- Implements the Unified Harness Protocol (UHP), an open standard, and exposes an OpenAI Responses-compatible API
- Products can run tasks, retrieve results, and switch harnesses through one API without handling harness engineering themselves
- Handles persistent sessions, streaming, files, cancellation, and failure handling out of the box
- Community Edition is Apache-2.0, self-hosted, with your keys and your infrastructure; 1.5k stars on GitHub
Related event: HarnessRouter: Routing Agent Harnesses Instead of Models(2 posts)→
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