HarnessesReference implementation
Independent resource · Not affiliated with HarnessRouter · Site data checked 21 Aug 2026
Reference implementation

HarnessRouter Community Edition

What is part of UHP, what is specific to HarnessRouter, and what the current self-hosted reference implementation actually supports.

Verified: Protocol: 2026-08-11Static HTML/CSS

What HarnessRouter Community Edition is

HarnessRouter Community Edition is the self-hosted reference implementation of UHP in the same public repository as the protocol. The project describes it as a single-container system that runs complete agent harnesses through a shared API while keeping provider keys and durable state on infrastructure controlled by the operator.

Current implementation snapshot

AreaVerified state
Latest observed tagv0.8.3, dated 23 Aug 2026
UHP protocol version2026-08-11
Harness backendsClaude Code, Codex, Hermes, Pi and DeepSeek Harness (dsh)
DeploymentSelf-hosted Docker container with persistent state on a volume
Conformance roleReference implementation; the protocol directory contains the conformance suite and published report evidence

Post-v0.8.0 developments: releases and main

Verified developments after v0.8.0. Reachability was checked against the tags: the conformance-suite hardening and integration fixes first mislabelled as "unreleased" on 22 Aug actually shipped with v0.8.1. As of 23 August 2026 only the Claude-plugin work remains unreleased main development (cutoff commit 95b96d7). None of this changes the UHP protocol version.

DevelopmentStatusWhat changed
Claude Code plugins (--plugin-dir) + stdio MCP serversmainunreleasedRunner-side materialization of Claude Code plugins via --plugin-dir plus stdio MCP server configuration, with tests (merge 95b96d7, PR #22). Post-dates v0.8.3; HarnessRouter integration work, not Anthropic adoption of UHP.
Session write-wall + scratch compatibility + vision routingReleased in v0.8.2 (23 Aug 2026)Self-hosted agent processes run under per-session UIDs and can write only their own session directory; shared scratch paths stay writable at mode 1733 for tools such as LibreOffice. Hermes image questions route to whichever instance integration serves a vision model, independent of the writing model. A Full-class UHP run of 52/52 is documented for this tree in commit messages.
Self-host share-link fixReleased in v0.8.3 (23 Aug 2026)Share links resolve without a hosted graph URL (SQLite backing) and pass the console login gate; the gateway still scopes disclosure to an enabled share token and only that session, and disabling sharing revokes resolution.
Workspace registry server-sideReleased in v0.8.1 (21 Aug 2026)The self-host workspace list moved from browser localStorage into the gateway store, so two browsers on one instance agree on what exists; browser-minted ids are adopted verbatim during migration.
Conformance suite revision 2026.8.11.post1Released in v0.8.1 (verified reachable from the tag)JSON conformance reports became strict: a skip is no longer a pass (conformant vs conformant_with_skips, skipped_not_verified, suite_version/generated_at, strict highest_class_passed). Total remains 52 checks.
Failed Response error envelope fixReleased in v0.8.1 (verified reachable from the tag)A failed Response now carries a spec-valid Error object (type from the closed enum plus a specific code: turn_failed, connections_exhausted, unhandled_exception); previously every failed turn was schema-invalid.
Hermes loopback relay normalizationReleased in v0.8.1 (verified reachable from the tag)OpenAI-legal message shapes that aggregator translation rejects are repaired before the provider sees them; the provider credential stays in the runner. Documented patched full-class runs: 52/52 via TokenRouter and LLMTR.
DeepSeek Harness reasoning_effort handlingReleased in v0.8.1 (verified reachable from the tag)Aggregator rejections of reasoning_effort are retried once without it, then stripped for the turn; documented LLMTR run improved from 47/52 to 52/52.

See the conformance page for what the post1 report fields mean for evaluating third-party claims, and the release tracker for the dated ledger.

Backend and provider routing

The repository currently documents multiple provider paths across the five supported harness backends: Claude Code, Codex, Hermes, Pi and DeepSeek Harness (dsh). This is a HarnessRouter provider/backend compatibility matrix, not a requirement of UHP itself.

Provider connectionBackends documented as compatible
AnthropicClaude Code, Hermes, Pi
OpenAICodex, Hermes, Pi
OpenRouterCodex, Hermes, Pi, DeepSeek Harness
Azure FoundryCodex, Hermes, Pi
Amazon BedrockClaude Code, Hermes
TokenRouterClaude Code, Codex, Hermes, Pi, DeepSeek Harness
Vercel AI GatewayClaude Code, Codex, Hermes, Pi, DeepSeek Harness
LLMTRClaude Code, Codex, Hermes, Pi, DeepSeek Harness

UHP features vs HarnessRouter product features

CapabilityWhere it belongs
Harness execution, sessions, streaming, cancellation, files and standardized errorsUHP protocol surface
Running Codex, Claude Code, Hermes, Pi and DeepSeek Harness behind one implementationHarnessRouter Community Edition
Provider routing and model-provider connection policiesHarnessRouter implementation
Slides, Sheets, Dashboards and Videos starter kitsHarnessRouter product examples, not UHP requirements
Media routing, video timeline and image importHarnessRouter product capabilities
Why the distinction matters: a UHP-compatible server can implement the protocol without cloning HarnessRouter's UI, starter kits, provider catalog or media features. Those product capabilities demonstrate what can be built around the execution contract; they do not redefine the standard.

Starter kits now documented

The current repository describes four worked product examples: Slides, Sheets, Dashboards and Videos. Each combines an app surface with an agent/harness configuration and a skill that teaches the agent how to produce the target artifact or workflow.

Security and deployment notes

The self-hosted documentation recommends loopback-only exposure for the default local start, changing the default password before exposing the service, and using least-privilege database credentials for dashboard connections. Treat these as implementation deployment guidance, not protocol-level security guarantees.

Primary sources