From an empty GitHub repository to a shipped pull request — in one guided loop.
Tip
This is the one guaranteed path. You will build a tiny app, run every command in the core loop exactly once, and — the part most tutorials skip — understand why each step exists. This tutorial uses Claude Code; GSD works in 15+ runtimes — see Install on your runtime for the flag and command syntax for yours.
- The one idea that makes GSD click
- What you'll build
- Prerequisites
- Step 1 — Install GSD Core
- Step 2 — Open Claude Code
- Step 3 — Create the project
- Step 4 — Discuss Phase 1
- Step 5 — Plan Phase 1
- Step 6 — Execute Phase 1
- Step 7 — Verify the work
- Step 8 — Ship it
- Glossary · Troubleshooting · What next
GSD Core does not "write your whole app in one shot." It runs a repeating five-step loop, and it does the heavy thinking in fresh, throwaway sub-agents so your main chat window never fills up with clutter — the quality killer GSD calls context rot.
You drive that loop one phase at a time:
flowchart LR
D([💬 Discuss]) --> P([📐 Plan])
P --> E([⚙️ Execute])
E --> V([✅ Verify])
V --> S([🚀 Ship])
S -. next phase .-> D
classDef step fill:#1f2430,stroke:#f0883e,stroke-width:2px,color:#e6edf3;
class D,P,E,V,S step;
| Step | Command | In one sentence | Typical time |
|---|---|---|---|
| 💬 Discuss | /gsd-discuss-phase |
GSD asks how to build it and writes your answers down. | 2–4 min |
| 📐 Plan | /gsd-plan-phase |
GSD splits the work into small, checkable task plans. | 1–5 min |
| ⚙️ Execute | /gsd-execute-phase |
Fresh agents write the code and commit each task. | 2–6 min |
| ✅ Verify | /gsd-verify-work |
GSD walks you through "does it actually work?" | 1–3 min |
| 🚀 Ship | /gsd-ship |
A pull request is opened for you. | <1 min |
Note
Keep that table handy. Whenever you feel lost, ask yourself one question: "which step of the loop am I on?" That's the entire mental model.
🧠 Why fresh sub-agents? (the 30-second version)
A single long chat slowly degrades: the more it holds, the more the model
juggles, and quality quietly drops. GSD sidesteps this by spawning a clean
200k-token worker for each heavy job (research, execution) and throwing it away
after. Your main session stays lean; the shared .planning/ files carry memory
between them.
flowchart TB
subgraph main [Your main session · stays lean]
you([You + GSD])
end
subgraph workers [Fresh sub-agents · clean context each time]
r1[Researcher]
r2[Researcher]
ex[Executor A]
ey[Executor B]
end
you -- spawns --> r1 & r2 & ex & ey
r1 & r2 & ex & ey -- write --> plan[(.planning/ files)]
plan -- memory --> you
classDef m fill:#132a1a,stroke:#3fb950,color:#e6edf3;
classDef w fill:#1f2430,stroke:#58a6ff,color:#e6edf3;
classDef f fill:#2d2410,stroke:#f0883e,color:#e6edf3;
class you m; class r1,r2,ex,ey w; class plan f;
A small Node.js command-line to-do app:
todo add "buy milk" # ➕ add an item
todo list # 📋 see open items
todo done 1 # ✅ complete item 1Items live in a local todos.json. It uses only the Node.js standard library
— nothing to install, nothing to configure — so you focus entirely on the GSD
loop, not a toolchain.
Tip
Small on purpose. Once the loop is muscle memory, the exact same eight steps scale to a real multi-phase product.
| You need | Check with | "Good" looks like |
|---|---|---|
| Node.js 22+ | node --version |
v22.x.x or higher |
| npm 10+ | npm --version |
10.x.x or higher |
| Claude Code | claude --version |
installed and opens |
| Git | git --version |
installed |
| GitHub CLI | gh --version and gh auth status |
installed and authenticated |
| An empty GitHub repository cloned locally | git remote get-url origin |
your repository's GitHub URL |
| Internet | — | available for installation and GitHub operations |
If you do not already have an empty repository, create and clone one now. If
gh auth status says you are not logged in, run gh auth login first.
gh repo create gsd-todo-tutorial --private --clone
cd gsd-todo-tutorial
git remote get-url originflowchart LR
A[node --version ≥ 22?] -->|no| A1[Install/upgrade Node] --> A
A -->|yes| B[npm --version ≥ 10?]
B -->|no| B1[Install/upgrade npm] --> B
B -->|yes| C[Claude Code installed?]
C -->|no| C1[Install Claude Code] --> C
C -->|yes| D[gh authenticated?]
D -->|no| D1[Run gh auth login] --> D
D -->|yes| E[origin points to GitHub?]
E -->|no| E1[Create or clone a repository] --> E
E -->|yes| R([✅ Ready for Step 1])
classDef ok fill:#132a1a,stroke:#3fb950,color:#e6edf3;
class R ok;
From a terminal in your project directory, run the installer:
npx @opengsd/gsd-core@latest --claude --localThis tutorial uses --local, so GSD is installed only in this project. On a
different runtime? See Install on your runtime
for its flag. You'll see a summary of what was installed, e.g.:
✓ Installed 71 commands to commands/ (gsd-<cmd>.md flat form)
✓ Installed agents
Then restart Claude Code so it picks up the new commands and agents.
💡 What just happened?
A .claude/ directory in your project now holds GSD's commands and
agents. You never edit these by hand — the installer owns them and keeps them
in Claude Code's native format.
Warning
Don't copy files from agents/ or commands/ directly — that bypasses the
installer's transformations and produces schema errors or missing commands.
Always use the installer.
For this disposable tutorial project, open (or restart) Claude Code in your project directory with:
claude --dangerously-skip-permissionsYou'll land at a prompt ready for input.
Caution
The permissions flag is optional. It skips per-file confirmation while
GSD's sub-agents read and write files. Use it only for this throwaway tutorial
in an empty folder. To keep confirmations enabled, start with claude instead.
For real work, read the security model first.
💡 What just happened?
Claude Code opened in the project where Step 1 installed GSD. It loaded the
project-local .claude/ commands and agents, so /gsd-* commands are now
available at the prompt.
At Claude Code's prompt:
/gsd-new-project
The first question is always "What do you want to build?" Paste this:
A Node.js CLI tool for managing to-do items. Users run `todo add "buy milk"`,
`todo list`, and `todo done 1`. Items are saved to a local todos.json file.
No external dependencies — Node built-ins only.
Then answer the clarifying questions, choose No when asked "Research before planning each phase? (adds tokens/time)" (skip it for this small build), take the recommended defaults for workflow settings, and wait for the roadmapper (~1 min). Type Approve on the proposed roadmap:
Proposed Roadmap
1 phase | 4 requirements mapped | All v1 requirements covered ✓
| # | Phase | Goal | Requirements |
|---|----------|----------------------------------------|-----------------|
| 1 | Core CLI | add / list / done commands, todos.json | CLI-01 … CLI-04 |
💡 What just got created in .planning/?
flowchart TD
root[.planning/]
root --> PROJECT[PROJECT.md<br/>your description + requirements]
root --> REQ[REQUIREMENTS.md<br/>a REQ-ID per capability]
root --> ROAD[ROADMAP.md<br/>Phase 1 · status: pending]
root --> STATE[STATE.md<br/>session memory · where you are]
root --> CFG[config.json<br/>your workflow settings]
classDef f fill:#1f2430,stroke:#f0883e,color:#e6edf3;
class root,PROJECT,REQ,ROAD,STATE,CFG f;
These files are GSD's shared memory — they survive /clear, survive closing
your laptop, and let a fresh sub-agent pick up exactly where the last left off.
👉 Do this now: open .planning/ROADMAP.md. Phase 1 has a Goal,
Requirements, and Success Criteria — the observable behaviors execution
must deliver. This file is your map for the rest of the tutorial.
GSD is built around fresh contexts. Clear the window before each phase:
/clear
Then open the discussion:
/gsd-discuss-phase 1
GSD asks about your implementation preferences — how to build, not just what:
> How should done items be stored — mark them in place or move them?
Mark them in place with a "done" flag.
> Should `todo list` show completed items by default?
No, hide them unless --all is passed.
> What if todos.json doesn't exist yet?
Create it silently on first add.
It writes .planning/phases/01-core-cli/01-CONTEXT.md.
👉 Do this now: open that file → find ## Implementation Decisions. Those are
your words, captured. The planner reads this next, so every decision here flows
into the task plans.
Note
Why discuss before planning? Decide the small stuff up front and the plan is right the first time — instead of you correcting a wrong plan, choice by choice.
💡 What just happened?
/clear discarded the old chat context, then /gsd-discuss-phase 1 captured
your implementation choices in 01-CONTEXT.md. The next planner receives those
decisions without needing the earlier conversation.
/gsd-plan-phase 1
sequenceDiagram
participant You
participant GSD
participant PL as Planner
participant PC as Plan-checker
You->>GSD: /gsd-plan-phase 1
GSD->>You: Research before planning Phase 1: Core CLI?
You->>GSD: Skip research
GSD->>PL: 01-CONTEXT.md
PL-->>GSD: atomic task plans
GSD->>PC: verify each plan hits the goal
PC-->>You: plans saved ✓
GSD asks "Research before planning Phase 1: Core CLI?" — choose Skip research (same
as Step 3; this build is small and well-understood). A planner then turns
01-CONTEXT.md into atomic task plans, and a plan-checker verifies each
before saving.
💡 What just got created?
.planning/phases/01-core-cli/
01-01-PLAN.md ← Task: todos.json read/write helpers
01-02-PLAN.md ← Task: add / list / done commands
👉 Do this now: open 01-01-PLAN.md. Inside the <task> block: a name, the
files it touches, action steps, a <verify> command, and a "done" condition.
That <verify> isn't decoration — the executor runs it after writing code.
/gsd-execute-phase 1
GSD groups plans into waves (independent plans run in parallel), spawns a fresh 200k-context executor per plan, and commits each task atomically:
Wave 1 (parallel):
[Executor A] → 01-01-PLAN.md (read/write helpers) ✓ committed
[Executor B] → 01-02-PLAN.md (CLI commands) ✓ committed
[Verifier] Checking codebase against phase goals...
CLI-01 todo add ✓ CLI-03 todo done ✓
CLI-02 todo list ✓ CLI-04 --all flag ✓
Status: PASS
Run your app — your first visible result:
node todo.js add "buy milk"
node todo.js add "write tests"
node todo.js list # → both items
node todo.js done 1
node todo.js list # → only "write tests"🎉 Item 1 disappears from the default list after done. It works.
💡 What just got created?
.planning/phases/01-core-cli/
01-01-SUMMARY.md ← what Executor A built + committed
01-02-SUMMARY.md ← what Executor B built + committed
01-VERIFICATION.md ← requirement coverage: PASS
/gsd-verify-work 1
GSD reads the phase's SUMMARY.md files and turns their user-visible
deliverables into checkpoints. It presents one checkpoint at a time; the first
one looks like this (the test wording depends on what was built):
### CHECKPOINT: Verification Required
**Test 1: Add a to-do**
Running `node todo.js add "buy milk"` creates a pending item without errors.
---
**Type `pass` or describe what's wrong.**
Type pass when reality matches, or describe what differs. GSD records the
answer in 01-UAT.md and then presents the next checkpoint.
If a check fails, GSD diagnoses the root cause and writes a fix plan → re-run
/gsd-execute-phase 1, then /gsd-verify-work 1 again. (Result:
.planning/phases/01-core-cli/01-UAT.md.)
Note
Why a separate verify step? "The code was written" and "the code works" are different claims. Verify proves the second one before you open a PR.
💡 What just happened?
GSD turned the phase summaries into user-visible checks, recorded your answers
in 01-UAT.md, and routed any failure back through a concrete fix plan. Shipping
only starts after those checks match reality.
/gsd-ship 1
GSD creates a pull request with a generated body (Summary · Changes · Requirements Addressed · Verification · Key Decisions):
Pull request created: https://github.com/your-org/your-repo/pull/1
Title: Phase 01: core-cli
That's the full loop — idea → opened PR — for one phase, start to finish. 🚀
flowchart LR
idea([💡 idea]) --> loop
subgraph loop [one phase]
direction LR
d[Discuss]-->p[Plan]-->e[Execute]-->v[Verify]-->s[Ship]
end
loop --> pr([✅ Pull request])
classDef a fill:#1f2430,stroke:#f0883e,color:#e6edf3;
classDef ok fill:#132a1a,stroke:#3fb950,color:#e6edf3;
class d,p,e,v,s a; class pr,idea ok;
💡 What just happened?
/gsd-ship 1 assembled the completed phase's requirements, decisions, and
verification evidence into a pull request. The PR is open for review; nothing
has been merged into the default branch yet.
For a multi-phase project, repeat Steps 4–8 for each phase. Not sure what's next? Let GSD detect it:
/gsd-progress --next
| Term | Meaning in GSD |
|---|---|
| Runtime | Your AI coding tool. This tutorial uses Claude Code. |
| Phase | One slice of the roadmap you take through the whole loop. |
| The loop | Discuss → Plan → Execute → Verify → Ship. |
| Sub-agent | A fresh, throwaway worker GSD spawns for research or execution. |
| Context rot | Quality decay as the main window fills up; fresh sub-agents prevent it. |
.planning/ |
GSD's shared memory: PROJECT, REQUIREMENTS, ROADMAP, STATE, per-phase files. |
| Requirement (REQ-ID) | A single v1 capability the roadmap must cover, e.g. CLI-01. |
| Success criteria | Observable behaviors a phase must deliver, checked in Verify. |
| Wave | A batch of independent task plans executed in parallel. |
| Symptom | Likely cause | Fix |
|---|---|---|
| A GSD command isn't recognized | Claude Code not restarted after install | Restart Claude Code so it loads the new /gsd-* commands. |
Spawning researchers… looks stuck |
Research runs 1–5 min | Wait — don't interrupt. If truly hung, /clear and re-run the step. |
| Verify keeps failing | Real bug in the code | Let GSD write the fix plan → /gsd-execute-phase 1 → re-verify. |
| Lost track of where you are | — | Open .planning/STATE.md, or run /gsd-progress --next. |
| Wrong install directory | Alternate/prerelease Claude Code config dir | Set CLAUDE_CONFIG_DIR to match — see Install on your runtime. |
- Install on your runtime — exact steps for every supported runtime
- The phase loop — why it's shaped this way
- Context engineering — the theory behind fresh sub-agents
- Configure model profiles — quality / balanced / budget tiers
- Onboarding an existing codebase — bring GSD to a brownfield repo
Tip
You now know the whole loop. Everything else in GSD is a refinement of these eight steps. Welcome aboard. 🚀