This is the hands-on companion to How I Use AI for Product Work and How My AI Product Second Brain Evolved. Those posts explain the philosophy; this one gets you to a working OpenCode setup in 30 minutes.

By the end, you’ll have a folder structure, three useful slash commands, and a context file that makes the AI actually useful.

Prerequisites

You’ll need OpenCode installed and configured. Follow the installation guide to get started. If you can run opencode in your terminal and get a response, you’re ready.

Step 1: Create the Folder Structure

Create a new directory for your product second brain. I recommend keeping it in a git repo so you can version your prompts over time.

mkdir -p product-ai/{context,prompts/pm,.opencode/command}
cd product-ai
git init

Your structure should look like this:

product-ai/
├── .opencode/
│   └── command/       # Slash commands live here
├── context/           # Personal context files
├── prompts/
│   └── pm/            # PM-specific prompts
├── AGENTS.md          # Instructions for OpenCode
└── opencode.jsonc     # OpenCode config

Step 2: Create Your Context File

The context file tells the AI who you are and how you work. Create context/about-me.md:

# About Me

## Role
[Your title] at [Company], working on [your area].

## What I Care About
- [Your product philosophy, e.g., "Start with the problem, not the solution"]
- [Your working style, e.g., "Bias toward shipping and learning"]
- [Your communication preferences, e.g., "Direct feedback, no hedging"]

## Current Focus
- [Project or initiative 1]
- [Project or initiative 2]

Keep this updated as your focus changes. The more specific you are, the more useful the AI becomes.

Step 3: Create AGENTS.md

This file tells OpenCode how to behave in your repo. Create AGENTS.md in the root:

# Product AI Second Brain

Read this file before responding.

## Who I Am
Read `context/about-me.md` for personal context.

## Slash Commands
Run these by typing the command in OpenCode:

| Command | Purpose |
|---------|---------|
| `/prd` | Review a PRD |
| `/debate` | Stress-test a product idea |
| `/okr` | Review OKRs |

Step 4: Add Your First Commands

Slash commands are markdown files in .opencode/command/. Each command file is a thin wrapper that points to a full prompt file in prompts/pm/. This separation keeps commands simple while allowing prompts to be detailed and shareable.

Command 1: /debate (Stress-test an Idea)

Create .opencode/command/debate.md:

---
description: Stress-test a product idea with pro vs skeptic debate
---

# Product Debate

Read these files before proceeding:
- `prompts/pm/debate-product-idea.md` - **REQUIRED: Full debate framework**
- `context/about-me.md` - Your product beliefs and context

## Your Task

$ARGUMENTS

## Instructions

Then create the prompt file prompts/pm/debate-product-idea.md with your full debate methodology. The basic structure: define two personas (a Visionary who argues for the idea and a Skeptic who pokes holes), have them debate, then synthesize the strongest arguments from both sides.

Command 2: /okr (Review OKRs)

Create .opencode/command/okr.md:

---
description: Review OKRs for clarity and outcome-orientation
---

# OKR Review

Read these files before proceeding:
- `prompts/pm/review-okrs.md` - **REQUIRED: Full OKR review framework**
- `context/about-me.md` - Your product beliefs and context

## Your Task

$ARGUMENTS

## Instructions

Then create prompts/pm/review-okrs.md with your OKR criteria. Mine checks for outcome-orientation (are these outputs or outcomes?), measurability, and whether the key results actually ladder up to the objective.

Command 3: /prd (Review a PRD)

Create .opencode/command/prd.md:

---
description: Review a PRD for completeness and clarity
---

# PRD Review

Read these files before proceeding:
- `prompts/pm/review-prd.md` - **REQUIRED: Full PRD review framework**
- `context/about-me.md` - Your product beliefs and context

## Your Task

$ARGUMENTS

## Instructions

Then create prompts/pm/review-prd.md with your PRD review criteria.

Step 5: Try It Out

Navigate to your product-ai directory and run OpenCode:

cd product-ai
opencode

Test each command:

/debate Should we build a self-serve dashboard for customers to debug their own issues?

/okr [paste your OKRs here]

What’s Next

Once you’re comfortable with this setup, consider adding:

• More commands: /retro for retrospectives, /feedback for drafting colleague feedback
• Skills: Methodology files that OpenCode loads automatically based on context (see the skills documentation)
• Daily summaries: A /today command that summarizes what you worked on
• Project-specific context: Folders for major initiatives with their own context files

The key is to start small and add complexity as you identify repeated workflows. If you find yourself doing the same thing more than twice, it’s probably worth automating.

If you build something useful on top of this, I’d love to hear about it!