Core concepts

Zozo's vocabulary is deliberate and consistent across code, issues, and these docs. This page introduces the terms most readers need first; the full glossary lives in the project's CONTEXT.md.

Harness

The orchestration layer Zozo builds. It spawns and coordinates agent sessions but never calls model APIs directly.

Provider

An adapter around a vendor agent runtime (Claude Agent SDK, Codex CLI) that owns its own inner agentic loop — not a raw LLM API client.

Runtime

The vendor-supplied agent executable or SDK a Provider wraps. It owns tool execution and context handling for its own turns.

Thread

The durable unit of conversation state. The harness store — not the Runtime's own native session — is the source of truth for a Thread; a Runtime's native session is a disposable cache. A Thread is pinned to one Provider.

Run

One execution of a Thread against its Provider. A Run's output is a sequence of normalized Events appended to that Thread's journal.

Event

The atomic, append-only journal record. Streaming, resume, durability, and rendering are all reads of this journal — there is no separate "final response" store.