Home / UHP Glossary: Agent Harness, Session, Response, Conformance

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UHP glossary

Short definitions for the terms used across the Unified Harness Protocol specification and this independent guide.

Verified: 21 Aug 2026Protocol: 2026-08-11Static HTML/CSS

Core UHP terms

Agent harness: A complete agent runtime around a model, including its execution loop, tools and session state.
Base: A stable identifier for a harness family, such as codex, claude-code or hermes.
Configured harness: A harness base plus runtime configuration such as model defaults, instructions, restrictions, skills, MCP servers and budgets.
Client: The application speaking UHP to request work.
Server: The UHP implementation that accepts tasks and drives one or more harnesses.
Response: One atomic unit of work: a task request and its resulting state/output.
Session: A chain of responses sharing conversation context, workspace and configured harness.
Container: The file namespace associated with a session.
Artifact: A file produced by agent work and made available through the protocol.
Event: A streamed fact describing progress, delivered through the event stream.
Conformance class: Core, Extended or Full; each class defines a cumulative set of mandatory server capabilities.
Capability discovery: The server document at GET /v1/uhp describing versions, conformance class and supported features.

MCP: Model Context Protocol, an open protocol for connecting AI applications to tools, resources and prompts. It addresses a different boundary from UHP.
Harness Protocol: A separate project for portable harness configuration using harness.yaml.
AHP: Agent Harness Protocol, a separate project oriented around agent/harness supervision events and policy decisions.
Pi: An upstream agent harness integrated by HarnessRouter Community Edition as a backend (v0.7.0). HarnessRouter also installs an MCP adapter for this path. Pi integration is a HarnessRouter implementation fact, not proof that the Pi project adopted UHP natively.
DeepSeek Harness: An upstream open-source agent harness from DeepSeek AI (developer preview, MIT licensed) integrated by HarnessRouter Community Edition as the dsh backend (v0.8.0). Integration is not proof of native UHP adoption by DeepSeek.
LLMTR: A Turkey-hosted model gateway added by HarnessRouter v0.6.0 as a provider. It is a HarnessRouter provider integration, not a UHP protocol feature.