OpenCode Agent Rules

Base OpenCode agent rules for execution discipline, verification, CLI-first scaffolding, and context window management.

This repo is intentionally not an SDD workflow kit. It is the base behavior layer used by any project.

Layers

Use this with higher-level workflow kits:

opencode-agent-rules        # base behavior, verification, context policy
        ↓
sdd-multiagent-opencode     # SDD commands, agents, skills, specs
        ↓
external UI skills          # impeccable, taste, nothing-design, etc.

Contents

AGENTS.md
opencode.json
.opencode/
├── rules/
│   ├── core-behavior.md
│   ├── status-verification.md
│   ├── cli-first.md
│   └── context-budget.md
└── plugins/
    └── context-guard.js

Install

Plugin Install (Recommended)

Add to your opencode.json (global or project-level):

{
  "plugin": [
    "@tudeorangbiasa/opencode-agent-rules@latest"
  ]
}

Restart OpenCode. The plugin auto-registers rules, agents, and context management.

To pin a specific version:

{
  "plugin": [
    "@tudeorangbiasa/[email protected]"
  ]
}

Why npm instead of GitHub? GitHub installs pull the latest commit which may include beta/unstable changes. npm packages are versioned and tested before publish, so you get a stable, mature release.

npx Install (Fallback)

For projects that prefer local files instead of a plugin:

cd your-project
npx -y -p @tudeorangbiasa/opencode-agent-rules init-rules

Manual Copy

cp AGENTS.md /path/to/project/
cp -r .opencode/rules /path/to/project/.opencode/
cp -r .opencode/plugins /path/to/project/.opencode/

Then merge opencode.json into the project's opencode.json.

Compaction Model

Configure the compaction model in one global plugin config:

~/.config/opencode/opencode-agent-rules.json

Free-tier default:

{
  "agent": {
    "compaction": {
      "model": "opencode/nemotron-3-super-free",
      "temperature": 0.1
    }
  }
}

Run opencode models opencode | grep "free" to verify current free model availability.

Restart OpenCode after editing the global config.

Context Budget

• 60%: reduce context and checkpoint.
• 80%: preserve state for compaction.
• Compaction must preserve current goal, source-of-truth files, decisions, files touched, verification state, blockers, and next action.

Related

• sdd-multiagent-opencode: SDD workflow layer.
• Impeccable / Taste / Nothing Design: optional UI skill layers.