Nexus Agents

Nexus Agents

Governance substrate for your AI coding agents — adversarial review, drift-detected rules, immutable audit, closed-loop telemetry

Why Nexus Agents?

Nexus-agents is a governance layer that sits above your AI coding agents — Claude Code, Codex, Gemini, and OpenCode. The agents do the engineering; nexus-agents enforces the rules they have to follow, reviews their work adversarially before it ships, audits everything they touch, and routes the next task based on what actually worked.

What it gives you:

• Adversarial PR review — pr_review runs 5 voter roles (architect, security, devex, catfish, scope_steward) with a 4-point verification gate. On the v5 evaluation set (10 PRs): 100% bug-catch and 50% raw false-positive rate; manual triage reclassified most "FPs" as legitimate findings the dataset had mislabeled. Full numbers: docs/research/pr-review-experiment-results-v5.md
• Drift-detected charter — CLAUDE.md + governance:check + blocking CI gates fail the build when documented rules drift from registered behavior (model registry, MCP tools, expert types, skills)
• Immutable audit trail — every tool call, every voter decision, every routing choice flows through AuditTrail with structured logging and hash-chained append-only storage; integrity is verifiable via the verify_audit_chain MCP tool
• Closed-loop routing — OutcomeStore feeds production telemetry back into LinUCB + TOPSIS scoring so the system actually learns from what shipped vs what regressed
• Multi-voter consensus — consensus_vote runs a default 7-role panel (architect, security, devex, ai_ml, pm, catfish, scope_steward; --quick uses 3). Six strategies: simple/super-majority, unanimous, higher-order Bayesian, opinion-wise, proof-of-learning

You:               "Review this PR / orchestrate this task / vote on this proposal"
                    ↓
nexus-agents:       enforce rules → route → adversarial review → audit → learn from outcome
                    ↓
Engineering agents: Claude Code · Codex · Gemini · OpenCode
                    ↓
Code:               actual edits, tests, PRs, issues

What this is NOT:

• Not another autonomous coding agent. OpenHands, SWE-agent, AutoGen, Devin, Factory — those are agents. Nexus-agents is the layer above them. Use whichever agents fit; we govern them
• Not a chat framework. Nothing here orchestrates conversations. It orchestrates real CLI tool invocations with real file I/O and outcome tracking
• Not a model API proxy. The value is the rules, the gates, the audit, and the learning. Routing is a side effect of the governance work, not the product

Where nexus-agents sits in your stack

   Human / IDE / CLI
   (Claude Code, Cursor, VS Code, terminal)
            │ MCP Protocol
            ▼
  ┌─────────────────────────────────────────────────────┐
  │  GOVERNANCE SUBSTRATE — what nexus-agents provides   │
  │                                                       │
  │   Charter (drift-checked)   Adversarial PR review    │
  │   Role registry             Multi-voter consensus    │
  │   Immutable audit trail     Closed-loop telemetry    │
  │                                                       │
  │   38 MCP tools · multi-stage CompositeRouter         │
  └────────────────────────┬────────────────────────────┘
                           │
                           ▼ delegates execution to
  ┌─────────────────────────────────────────────────────┐
  │  ENGINEERING AGENTS — what does the actual work      │
  │                                                       │
  │   Claude Code · Codex · Gemini · OpenCode            │
  └────────────────────────┬────────────────────────────┘
                           │
                           ▼ produces
                   Code, tests, PRs, issues

The governance substrate is the layer that catches the mistakes engineering agents would otherwise make — bad code shipped, rules drifting from intent, audit gaps, telemetry-free routing — and routes the next task based on what actually worked the last time.

Quick Start (2 minutes)

1. Install

npm install -g nexus-agents

Or as a Claude Code plugin (single-command install from the official marketplace):

/plugin install nexus-agents

See docs/getting-started/PLUGIN_INSTALL.md for plugin-specific setup, or llms-install.md for the short install guide an AI agent can follow.

2. Verify

nexus-agents doctor

3. Use

With Claude Code (recommended):

nexus-agents setup   # Auto-configures MCP server

Then in Claude: "orchestrate: Review this PR for issues"

Standalone CLI:

export ANTHROPIC_API_KEY=your-key
nexus-agents orchestrate "Explain the architecture of this codebase"

Security: In default MCP mode, the server communicates only via stdio with the parent process (no network exposure). The REST API (opt-in) auto-generates an API key on first start. For network-exposed deployments, set NEXUS_AUTH_ENABLED=true. See SECURITY.md.

Capabilities

Available Experts

Supported CLIs & Providers

Nexus-agents routes tasks through 5 CLI adapters, each connecting to major AI providers:

CLI Commands

nexus-agents                    # Start MCP server (default)
nexus-agents doctor             # Check installation health
nexus-agents setup              # Configure Claude CLI integration
nexus-agents orchestrate "..."  # Run task with experts
nexus-agents vote "proposal"    # Multi-agent consensus voting
nexus-agents review <pr-url>    # Review a GitHub PR
nexus-agents expert list        # List available experts
nexus-agents workflow list      # List workflow templates
nexus-agents config init        # Generate config file
nexus-agents init --portable    # Create workspace-local .nexus-agents/ for sandboxes
nexus-agents init --portable --mcp-config  # Also emit .mcp.json wiring Claude Code to it
nexus-agents init --portable --install --mcp-config  # …and install the binary into the workspace
nexus-agents fitness-audit      # Run fitness score audit
nexus-agents research query     # Query research registry
nexus-agents --help             # Full command list

See docs/ENTRYPOINTS.md for the complete CLI reference (28+ commands).

MCP Tools

When running as an MCP server, the following tools are available:

Configuration

Environment Variables:

Generate config file:

nexus-agents config init   # Creates nexus-agents.yaml

Documentation

Development

git clone https://github.com/nexus-substrate/nexus-agents.git
cd nexus-agents
pnpm install
pnpm build
pnpm test

Requirements: Node.js 22.x LTS, pnpm 9.x

Contributing

1. Fork the repository
2. Create a feature branch (git checkout -b feat/amazing-feature)
3. Commit with conventional commits (feat(scope): add feature)
4. Open a Pull Request

See CONTRIBUTING.md for details.

License

MIT - See LICENSE

Built with Claude Code