mgajewskik/opencode-config

OpenCode Configuration

Create commands, agents, prompts, modes, and AGENTS.md for OpenCode.

Decision Tree

Route user request to correct config type:

User wants to customize OpenCode behavior
│
├─ User-invoked action with arguments?
│  └─ Yes → COMMAND (load references/commands.md)
│
├─ Autonomous task handler / specialized persona?
│  └─ Yes → AGENT (load references/agents.md)
│
├─ Reusable system instructions for agents?
│  └─ Yes → PROMPT (load references/prompts.md)
│
├─ Session-wide behavior/tool toggle?
│  └─ Yes → MODE (load references/modes.md)
│
└─ Persistent rules across all sessions?
   └─ Yes → AGENTS.md (load references/agents-md.md)

Quick Reference

| Type | Purpose | Location | Invocation | |------|---------|----------|------------| | Command | User action with args | commands/*.md | /name args | | Agent | Specialized AI persona | agents/*.md | @name or auto | | Prompt | Reusable instructions | prompts/*.md | Referenced by agents | | Mode | Tool/behavior toggle | modes/*.md or JSON | Tab key | | AGENTS.md | Persistent rules | Root AGENTS.md | Always loaded |

Workflow

Step 1: Identify Config Type

Ask if unclear:

• "Should this be triggered by user (/command) or automatically?"
• "Is this a one-time action or persistent behavior?"
• "Does this need arguments from user?"

Step 2: Load Reference

Based on decision tree, load the appropriate reference file:

• Commands → references/commands.md
• Agents → references/agents.md
• Prompts → references/prompts.md
• Modes → references/modes.md
• AGENTS.md → references/agents-md.md

Step 3: Create Config

Follow patterns from loaded reference. Key principles:

• Commands: Instructions FOR the AI, not messages to user
• Agents: Include triggering examples in description
• Prompts: Keep reusable, reference via {file:./prompts/name.md}
• Modes: Focus on tool permissions
• AGENTS.md: Concise rules, not tutorials

Step 4: Place File

Global (all projects):

• ~/.config/opencode/commands/
• ~/.config/opencode/agents/
• ~/.config/opencode/prompts/
• ~/.config/opencode/modes/
• ~/.config/opencode/AGENTS.md

Project-specific:

• .opencode/commands/
• .opencode/agents/
• .opencode/prompts/
• .opencode/modes/
• ./AGENTS.md

Common Patterns

Command for User Action

---
description: Brief description for /help
---

Do X with $ARGUMENTS.

[Instructions for AI...]

Agent for Specialized Task

---
description: Use when [trigger]. Do NOT use for [anti-trigger].
mode: subagent
model: inherit
tools:
  write: false
  edit: false
---

You are [role]. Focus on [responsibilities].

[Process steps...]

Prompt for Reusable Instructions

You are [role]. Your task is to [objective].

[Detailed instructions...]

Referenced by agent: "prompt": "{file:./prompts/name.md}"

Mode for Behavior Toggle

---
description: Mode description
tools:
  write: true
  bash: false
---

[Instructions when in this mode...]

AGENTS.md for Persistent Rules

## Section Name

**Rule in bold.**

- Specific instruction
- Another instruction

[Keep concise, actionable]

NEVER

• Create commands that message user instead of instructing AI
• Create agents without triggering examples in description
• Put "when to use" in agent body instead of description
• Create verbose AGENTS.md with tutorials
• Use Claude Code-specific features (argument-hint, allowed-tools)

ALWAYS

• Use $ARGUMENTS or $1, $2 for command arguments
• Include mode: subagent for non-primary agents
• Keep AGENTS.md rules actionable and concise
• Test commands work with OpenCode syntax