Key Concepts

Before diving into Nexus OS, understand these fundamental concepts that appear throughout the documentation.

Agent

An agent is a self-contained unit of work. It receives input, performs a task, and produces output. Agents run in WASM sandboxes for isolation and security.

bash

naos create my-agent --template researcher

Orchestration Primitives

Nexus provides four ways to coordinate agents:

Primitive	Purpose	Analogy
Supervisor	Restart failed agents	A manager who rehires when someone quits
Saga	Multi-step with rollback	A transaction that undoes itself on failure
Workflow	Sequential pipeline	An assembly line where each station passes to the next
Pool	Parallel execution	A team working on the same task simultaneously

Supervision Tree

Supervisors can supervise other supervisors, creating a tree:

root-supervisor
├── api-supervisor
│   ├── auth-agent
│   └── data-agent
└── worker-supervisor
    ├── processor-1
    ├── processor-2
    └── processor-3

If processor-1 crashes, worker-supervisor restarts it. If worker-supervisor itself crashes, root-supervisor restarts it and all its children.

Cost Budget

Every agent can have a spending limit:

yaml

cost:
  budgets:
    researcher:
      limit: 1000    # cents ($10.00)
      period: day
      onExceed: pause

Trust Score

AXIS Trust assigns scores to agents:

T-Score: 0-100 (overall trustworthiness)
Trust Tier: T1-T5 (classification)
Credit Rating: AAA to D (transaction reliability)

WASM Sandbox

Agents compile to WebAssembly and run in an isolated sandbox. No file system access, no network access, no ambient authority — only what you explicitly grant.

Audit Log

Every action in Nexus OS is logged:

bash

naos audit --last 10

# [2025-01-15 10:30:01] agent.created    researcher
# [2025-01-15 10:30:02] agent.started    researcher
# [2025-01-15 10:31:15] cost.recorded    researcher  $0.05
# [2025-01-15 10:31:16] agent.completed  researcher

Project

A Nexus project is a directory containing:

nexus.config.yaml — Configuration
data/ — SQLite database
agents/ — Agent source files
skills/ — Skill definitions

Architecture Overview

Requirements