AI Developer Toolkit
Claude Code, Codex, Cursor.Ship what they write without reading every line.
400+ guides and 100+ recipes on setting up, briefing and checking coding agents, so what they build survives review and production. For Claude Code, Codex and Cursor, in English and Polish. Every guide shows when it was last updated.

The agent wrote it in ten minutes. Then your week started.
Most developers who work with coding agents hit the same wall. It is not the model. It is everything around it.
Review found it, not the agent.
The change worked in the chat and failed in the pull request. Thursday went on fixing what the agent should have tested itself.
Your setup lives in chat history.
The prompt that worked is somewhere in a scrollback. Nobody, you included, can run it again on Monday.
That flag does not exist.
A blog post said --approval-mode. Codex says there is no such flag. Half of what you read about these tools is a release behind.
You still read every line.
The agent writes most of the code and your job turned into reviewing it. That is faster than typing. It is not what you were promised.
Everyone online ships ten times faster, and you are in the review queue at eleven at night wondering what you are doing wrong. You are not. A tool that writes the code should not leave you reading all of it.
What it takes is a way of working around the tool: what you write down before it starts, what it has to prove before anything merges, and who signs off. Nobody ships that in the box.

Written from inside the review queue, not from a conference stage.
Michał Jaskólski · 26 years building web apps · 2 IPOs · AI Lecturer at SWPS University · Using Cursor since 2023, Claude Code and Codex since early beta · CTO at TasteRay (built with AI) · @jaskol_ski
Creator of wondel.ai Skills — 1.1k+ stars on GitHubEngineering teams at these companies use it
What you come here to do.
Every guide is filed under a job, for the tool you run, at the level you are at. Start with the one that costs you the most this week.
Set the tool up so it works on Monday, not after a weekend.
CLAUDE.md, AGENTS.md and Cursor rules, hooks, permissions, and MCP servers that actually exist. The Setup Pack generates the files for your repository.
Turn a request into something the agent cannot misread.
intent.md, spec.md and plan.md before the first line of code, with acceptance criteria the agent has to meet.
Get a pull request you can trust without reading every line.
Tests before review, evidence attached to the pull request, and gates the change has to pass whoever opened it.
Run agents unattended.
Isolated worktrees, loops with a stop condition, CI as the reviewer, and a human at the gate before production.
Do it in your stack.
100+ copy-paste recipes for React, Next.js, Vue, Node, Python, Go, Rust, databases, DevOps and mobile.
Pick a tool, or switch.
Cursor, Claude Code, Codex and GitHub Copilot side by side: features, pricing, and how to move between them.
Bring the team along.
One brief, one review standard, permissions and a rollout that do not depend on who opened the pull request.
Stay current without reading release notes for three tools.
New guides land in What’s new, and every guide shows when it was last updated, so you can see how old what you are reading is.
Read the guides from inside your agent.
The MCP server serves the library to Claude Code, Codex and Cursor, so the agent can look a workflow up while it works.
Where are you on the ladder?
Dan Shapiro’s six levels, from writing every line yourself to a factory that turns specs into releases. Most AI-native developers sit at Level 2, and most teams top out at Level 3. The free scorecard places you in about eight minutes, no account, and names the one change that moves you up.
- L0
By hand
You write the code. AI is a search engine at best.
- L1
Assisted
Autocomplete and pasted snippets. The agent never sees the repo.
- L2
Paired
One agent, one bounded task, with a human watching each step.
- L3
Review manager
Agents implement bounded plans; you review every diff, test and risk note.
- L4
Spec manager
Humans own intent, specifications and gates; agents execute isolated plans.
- L5
Dark factory
Agents pull work behind policy and CI; humans set priorities and handle exceptions.
What you get
- Your level on the ladder, 0 to 5.
- The stage that caps it: Plan, Design, Build, Test, Deploy or Maintain.
- The one change that lifts it, and a 30 / 60 / 90 plan.
Three steps, one real change.
- 01
Find your level.
Twenty-five questions on how you plan, build, test and ship with agents. About eight minutes, free, no account. You get your level and the one change that lifts it.
- 02
Start the trial. Install the Setup Pack.
Seven days, the whole library. Answer a few questions about your repository and the Setup Pack generates the context files, hooks and MCP configuration for your tool.
- 03
Ship one change the new way.
Something you were going to build anyway: brief, then diff, then tests, then review. Keep it if it holds up. If it does not, a first purchase is refundable for 30 days.
For you if. Not for you if.
For you if
- You already use Claude Code, Codex or Cursor and want what they write to hold up in review and production.
- Your setup lives in chat history and you want it in the repository.
- You use more than one of the three tools and want one way of working across them.
- You have never let an agent run unattended, because you would not trust the result.
Not for you if
- You want prompt tricks, and nothing about how work is specified or reviewed should change.
- You use AI for the occasional throwaway script.
- You will not own review, risk or production approval.
- You want no workflow files in the repository.
One subscription. Every level, all three tools.
Find your level free. Then every guide for the climb — Claude Code, Codex and Cursor — plus the Setup Pack and all four books, in one plan.
Solo Developer
For a developer who wants to stop reading every line the agent writes.
then $19.99 per month
Cancel anytime
- The Setup Pack — CLAUDE.md, AGENTS.md, Cursor rules and MCP config generated for your stack ($49 on its own)
- 400+ guides and 100+ recipes for Claude Code, Codex and Cursor, each showing when it was last updated
- All four books — 348 chapters, EPUB & PDF, English and Polish ($159 at list price)
- A spec before the diff and tests before the review — the same order in all three tools
- The Level 3 → 4 patterns: sandboxes, stop hooks and verification gates that let you stop reading every line
- Migration playbooks from Copilot or a plain IDE into the same way of working
- The Discord for questions, and a public GitHub repo for reporting a mistake you found
Team
One level for the whole team, inherited on day one.
then $199.99 per month
Cancel anytime
- Everything in Solo Developer, for every engineer
- Unlimited seats — by email domain, or by named address for teams spread across domains
- Shared brief templates, repository context and verification gates for every seat
- All four books for every seat — EPUB & PDF
- One company invoice with VAT
- Direct email support from the author
Enterprise
An audit of where your teams really are, a measured pilot — and someone accountable for adoption.
unlimited seats
- Everything in Team, unlimited seats
- An audit of how each team actually works with agents, across Plan, Design, Build, Test, Deploy and Maintain
- The brief chain installed: intent, spec, plan, repository instructions and CI evidence
- Hands-on workshops plus a pilot team, with adoption measured from day one
- A pilot under least-privilege tools, human production approval and incident feedback
- White-label or on-premise? Ask on the intro call.
- Delivered personally by the author
Created by @jaskol_ski
26 years building web apps · 2 IPOs · AI Lecturer at SWPS University · Using Cursor since 2023, Claude Code and Codex since early beta · CTO at TasteRay (built with AI)
The math
It pays for itself in 13 minutes.
Every guide is meant to save you more than that in one sitting. If one doesn’t — 30-day money-back guarantee on a first purchase.
How we compare
| Free YouTube | Official Docs | AI Developer Toolkit | |
|---|---|---|---|
| Content | Scattered, often outdated | Feature reference only | 400+ guides, Levels 0–5 |
| Freshness | Recorded once | Release notes only | Every guide shows when it was last updated |
| Path | Figure it out yourself | No guidance | A level to find, a rung to climb |
Content
- Free YouTube: Scattered, often outdated
- Official Docs: Feature reference only
- AI Developer Toolkit: 400+ guides, Levels 0–5
Freshness
- Free YouTube: Recorded once
- Official Docs: Release notes only
- AI Developer Toolkit: Every guide shows when it was last updated
Path
- Free YouTube: Figure it out yourself
- Official Docs: No guidance
- AI Developer Toolkit: A level to find, a rung to climb
What you actually get
The subscription, itemised.
Two of these are sold on their own, so their prices are checkable rather than claimed. The third is the subscription itself — nobody sells it separately, so it carries no number.
- The Setup Pack — repository context
- Your CLAUDE.md, AGENTS.md, Cursor rules and MCP config, generated for your stack, plus TESTING.md — shared repository context in about 20 minutes.
- Sold on its own for $49.
- $49Included
- The Book Library
- Four books, 348 chapters, EPUB and PDF — the cross-tool Handbook plus one deep book each on Cursor, Claude Code and Codex.
- Four titles listing at $39.99 each, rounded down. Both language editions are included.
- $159Included
- The Documentation Access
- Every guide for Levels 0–5, for Claude Code, Codex and Cursor — each showing when it was last updated.
- No separate price: this is the subscription itself, not an extra sold beside it.
- Not sold separately
- Downloadables
- $208
$208 of it, against $99.99 for a year.
What that access is worth is your own time: one hour of it costs more than two months of this.
Lifetime access closes 2026-10-01
After 2026-10-01 the lifetime plan is retired. Monthly and annual continue as normal. Everyone who already holds lifetime access keeps it.

Move the whole team up a level.
One brief, one review standard and one release gate for everyone, in every repo — Claude Code, Cursor or Codex. Either as a shared-seat subscription, or installed in your own repositories in a half-day workshop.
Team
Every guide for every engineer — one price, one invoice.
unlimited seats — email domain or named addresses
- Everything in Solo Developer, for every teammate
- Shared repository context for Claude Code, Cursor and Codex
- All four books (EPUB & PDF) for every seat
- Direct email support from the author
Team Enablement Workshop
A hands-on half-day that installs the shared brief and the gates in your own repositories.
half-day, live · up to 15 developers
- Live, hands-on session on your own repositories
- intent.md → spec.md → plan.md templates plus repository instructions
- The verification, review and production gates the team keeps afterwards
- 3 months of the Team plan for attendees included
Just for you? Start with an individual seat →
Common questions
Refunds, invoices, seats — and the questions the page above provokes.
You could, and it would sound right. Ask one about Codex approval modes and there is a good chance you get `--approval-mode`, which is not a flag — the real one is `--ask-for-approval`, and its values are `untrusted`, `on-request` and `never`. Copy the invented one and Codex rejects the command outright — you do not get a wrong permission posture, you get an agent that will not start. What you are paying for is that this list of invented flags is checked against a named release, with the version written next to each entry — and that the guides show when they were last updated. It matters more the higher you run: an agent you watch at Level 2 gets corrected in a minute; an agent left unattended for twelve hours on an invented flag is twelve hours of nothing, discovered in the morning. We keep a list of the ones models keep inventing.
At scale they already write most of it. Anthropic reports that more than 80% of the lines merged into its codebase in May 2026 were written by Claude, and Stripe merges over 1,300 pull requests a week with no human-written code (Stripe, February 2026). Across the industry the share is lower: DX measured 51.9% AI-authored code on average across more than 400 companies in Q2 2026. The other half of the evidence matters just as much. in METR’s controlled study, experienced developers’ tasks took 19% longer with AI on their own repositories (2025), and Faros AI measured incidents per PR up 242.7% alongside the throughput gains (April 2026). Which set your team gets depends on what the agent has to prove before merge — that is what the levels measure.
You own intent, architecture, acceptance criteria, risk, production approval and exception handling. Agents can research, propose, implement, test and prepare evidence, but accountability does not move to the model. The workflow makes those human decisions explicit instead of hiding them inside a chat.
That is the most common reason people cancel, so start with one real change. Use the Setup Pack to add repository context, write intent.md, spec.md and plan.md for something you were going to build anyway, and run it in your tool. You get one change done the new way before you read anything else. If it still is not for you, the 30-day first-purchase refund covers it.
Tool fluency is Level 2 or 3, not a level of trust. Ask whether every request becomes a committed intent, spec and plan; whether the agent runs isolated; whether a PR carries its own evidence; whether incidents update the next plan. Where the answer is no, that is the guide to read — for the tool you run, at the release you run.
The levels are Dan Shapiro’s Five Levels (January 2026): from Level 0, where you write everything, to Level 5, the dark factory, where agents pull work behind policy and CI. Level 2 is one agent, one bounded task, with you watching. Level 3 is agents implementing plans while you review every diff. Level 4 is you owning the spec and the gates while agents run unattended. The six stages — Plan, Design, Build, Test, Deploy, Maintain — are what you do at each level: the scorecard asks about them to place you, and the guides show the stage practice that moves you up one rung.
A tutorial usually teaches one feature in one tool, as of the day it was recorded. Here the guides sit on the ladder, cover all three tools, and each shows when it was last updated — so you can see how old what you are reading is.
Yes. From your account page, and access runs to the end of the period you paid for.
Yes — 30 days from your first purchase, for any reason. Email support@developertoolkit.ai and we refund it; we won't argue with you about why. Applies to first-time purchases, as set out in the Terms.
You keep full access until the end of the period you've already paid for — the subscription simply doesn't renew. Your account stays in place, so you can pick up where you left off anytime. Any ebooks you've downloaded are yours to keep.
Yes. Payments are handled by Polar, our merchant of record, which issues an invoice for every charge with the applicable VAT or sales tax for your country. It lands in your inbox right after payment — ready to expense or pass to your accountant.
Unlimited seats for one flat price. Everyone with an email address on your company domain gets full access automatically, and teams spread across domains can add named addresses instead — no per-seat billing, no invites to manage. Need white-label or on-premise? Ask on an Enterprise intro call.
The 100+ recipes cover React, Next.js, Vue, Python, Node.js, Go and Rust, and the ladder itself does not care what language you write — the brief chain, the verification gates and the MCP setup are the same in every stack. The recipes make it concrete in yours.
Still have questions? Contact us

Next quarter the agent still writes the code. Who reads it is up to you.
Keep reading every diff and you stay the bottleneck your agent is waiting on. Or spend seven days putting a brief, a test gate and a review standard into one repository, and see what the agent leaves behind when it has to prove its work.