From code to intent
For decades, programming has been an act of translation: understand the problem, design a solution, then render it in syntax — curly braces, semicolons, types. That friction is now collapsing. This guide summarizes the paper "The New SDLC With Vibe Coding" (Addy Osmani, Shubham Saboo & Sokratis Kartakis) in interactive form: quizzes, simulators and cheatsheets to help you master the transition from ad-hoc prompting to agentic engineering.
The goal: understand how AI is reshaping the SDLC and adopt these capabilities without sacrificing the discipline that production software demands. It assumes familiarity with modern development practices — not with the specifics of AI or machine learning.
AI Agents in 60 seconds
First, a shared vocabulary. A chatbot produces a response and waits. An agent runs its own loop: you give it a goal, and it decides the next step.
The climb: from autocomplete to autonomy
The agent loop — click each step
🎯 Perceive
The agent reads the current state: the goal it received, the available context, the result of the last action. It's the "scan the scene" step before deciding anything. → click the other steps in the diagram.
The 5 parts of every agent
The spectrum: vibe coding → agentic engineering
In Feb 2025, Andrej Karpathy described vibe coding: "fully give in to the vibes, forget that the code even exists." The term went viral — and became a confusing umbrella. In 2026, Karpathy himself proposed agentic engineering for the disciplined end. It's not a binary: it's a spectrum. The differentiator isn't whether you use AI — it's how much structure, verification and human judgment surrounds the output.
| Dimension | Vibe Coding | Structured AI-Assisted | Agentic Engineering |
|---|---|---|---|
| Intent specification | Casual natural-language prompts | Detailed prompts with examples and constraints | Formal specs, architecture docs, memory files |
| Verification | "Does it seem to work?" | Manual testing, spot-checking | Automated suites, CI/CD gates, LM judges |
| Codebase understanding | Minimal — the dev may not even read the generated code | Selective review of critical paths | Full review of architecture; AI handles the details |
| Error handling | Copy the error back into the prompt | Dev diagnoses the root cause, AI implements the fix | Agents self-diagnose within bounds; humans handle the architectural |
| Appropriate scope | Prototypes, scripts, personal projects, hackathons | Features within established codebases | Production systems, team-scale development |
| Risk profile | High — acceptable for disposable code | Moderate — human judgment at key checkpoints | Low — systematic verification at every stage |
Context engineering: the real skill
The quality of generated code depends less on prompt cleverness and more on the quality of the context provided. The question isn't "how do I trick the AI?" — it's: "what would a new team member need to know to contribute well, and how do I encode that?"
The 6 types of context every agent needs
Static × Dynamic: the architecture trade-off
📌 Static context
- System instructions and persona
- Rule files:
AGENTS.md, CLAUDE.md, GEMINI.md - Global project memory
Cost: every token is present in every interaction, relevant or not. Excess dilutes the signal.
⚡ Dynamic context
- Skills triggered by task matching
- Tool results retrieved during execution
- Documents via RAG, windowed session history
Efficiency: the agent pays the token cost only when the information is needed.
What is static and what is dynamic is a first-class architectural decision — reviewed and versioned like any other configuration. Too much static wastes tokens; too little and the agent forgets critical rules.
Agent Skills — the winning pattern (click the tabs)
The agent starts as a lightweight generalist. It sees only names and short descriptions of dozens of skills — without paying for the content:
skills_available: - deploy-agent: "deploy ADK agents to Agent Runtime" - eval-runner: "runs evalsets and reports regressions" - db-migration: "safe schema migrations" - legacy-refactor: "legacy code refactoring" ... (dozens more)
You request a deploy. The agent does matching with the skill deploy-agent and loads the full instructions for that skill — and only that one:
loading skill: deploy-agent ✓ pre-deploy checklist (env vars, permissions) ✓ publishing steps to Agent Runtime ✓ automatic rollback rules
Only if the task demands it, the agent pulls the deep reference material — the full API, edge cases, error tables. Progressive disclosure: each level costs more, but is only paid for when needed.
deep reference: deploy-agent/reference.md ✓ full agents-cli flags catalog ✓ permissions matrix per environment ✓ deploy incident runbook
Skills solve 4 classic problems: context rot (overloaded prompts), the lack of procedural memory in LLMs, the overhead of multi-agent architectures, and the need for portability across tools and vendors.
The new software development life cycle
AI compresses the cycle unevenly: implementation that once took weeks now takes hours, while requirements, architecture and verification remain at human pace. The result is not a faster old SDLC — it's a different workflow, with phases that blur and iteration cycles of minutes.
The compression (animated)
Phase by phase — explore
Requirements become a conversation
Historically, requirements was the phase with the widest gap between intent and implementation. Now AI participates directly in refinement:
- Generates user stories from product briefs
- Identifies edge cases that humans miss
- Produces API schemas from natural-language descriptions
- Generates interactive prototypes from specification documents
"generate user stories + acceptance criteria + 5 edge cases I didn't consider"Architecture remains ours
Architectural decisions are fundamentally about trade-offs: consistency × availability, complexity × flexibility, build × buy. They depend on business context, organisational constraints and long-term strategy that AI cannot fully grasp.
- AI excels at implementing architectural decisions once they are made
- Given a clear architecture doc, agents scaffold entire applications with consistent patterns
- Your role shifts from writing boilerplate to making and documenting the structural decisions
From writing to reviewing, guiding and verifying
Modern agents generate entire features from natural-language descriptions, complex algorithms, and coherent multi-file changes.
- Industry surveys report 25–39% productivity gains, with projections of 30–35% across the full process
- But the METR study found that experienced developers were 19% slower on certain tasks — due to time spent verifying, debugging and correcting AI output
- AI does not eliminate implementation work: it transforms it
Tests and evals: the language of intent
Testing AI-generated code requires evaluating not just what the agent produced, but how it got there:
- Output evaluation: the final artifact — does it compile? do the tests pass?
- Trajectory evaluation: the full sequence of tool calls and intermediate reasoning
- A fluent output that skipped its verification steps is a more dangerous failure than a visible error
- Agents generate test cases — including edge cases and property-based tests — that humans wouldn't think of
Augmented review, vigilant deployment
AI acts as a first-pass reviewer: potential bugs, style violations, security vulnerabilities and performance issues — before a human ever sees the code.
- It doesn't replace human review: decisions about design, maintainability and strategic alignment remain with us
- It drastically reduces the cognitive load on reviewers
- Agents monitor deployment health, perform automatic rollbacks, and predict risk based on the nature of the changes
Human: design, maintainability, strategy.
Legacy finally stops being untouchable
Legacy codebases that were impenetrable to new members can now be navigated, understood and modified with AI assistance.
- The agent reads the codebase, understands its patterns, identifies the relevant files, and implements while respecting the existing architecture
- Code that was "too risky to touch" can be refactored, modernized and extended safely
- Framework migrations, updating deprecated APIs, modernizing test suites — tasks that previously simply never happened
The factory model
The mental model that ties it all together: the developer's primary output is not the code — it's the system that produces code. A factory manager doesn't assemble every widget by hand: they design the assembly line and ensure quality control.
You design the system
Specifications, context, success criteria — not step-by-step instructions
Agents produce the code
They translate specs into implementation and iterate on their own within the boundaries
Tests verify the output
Quality gates and feedback loops route failures back for automatic correction
The 5 parts of your factory
Harness: what surrounds the model
It's tempting to treat the model as the system: "a new model came out, the agent got smarter." That intuition is wrong. The model is one input. Everything else — prompts, tools, context policies, hooks, sandboxes, sub-agents, observability — is the harness: the scaffolding that lets the model actually finish things.
a raw model is not an agent — it becomes one when the harness gives it state, execution, feedback and constraints
📜 Instructions & rule files
The text that defines who the agent is, what it cares about, and what it is forbidden from doing: AGENTS.md, CLAUDE.md, GEMINI.md, skill files and sub-agent prompts. It's the cheapest, highest-impact piece.
The harness in every SDLC phase
1 · Requirements & Architecture → Configuring the harness
Before any production code: create the AGENTS.md, define architectural constraints, choose the tools (APIs, schemas) and the unbreakable rules.
2 · Implementation → Running the harness
The model generates code and executes it inside the harness's isolated sandbox. Needs to read a file or fetch something? It uses the tools the harness provides — nothing beyond.
3 · Testing & QA → The feedback loop
Test failed? The orchestration captures the error from the sandbox and routes it back to the model, asking for another attempt. The harness creates the automatic think → act → observe loop.
4 · Review, Deployment & Maintenance → Observing the harness
Deterministic hooks block the commit with a hardcoded password. Observability tracks token cost, latency and drift — you audit why the agent decided what it decided.
On Terminal Bench 2.0, one team moved a coding agent up the ranking by changing only the harness — zero model change.
A LangChain study on the same benchmark: tweaks only to system prompt, tools and middleware around a fixed model.
Conductor × Orchestrator: your new role
Two working modes you'll fluidly alternate between. Neither is "better" — each serves a type of task.
The Conductor
- You're in the IDE, watching code appear, guiding with prompts and corrections
- Fine-grained control over every change
- Ideal for: complex logic, hard debugging, unfamiliar codebases
- Risk: if you dictate every keystroke, you become the bottleneck
The Orchestrator
- You define goals, delegate to agents and review results — without watching line by line
- Agents work in parallel, in the background, in sandboxes
- Ideal for: bug fixes, features against established patterns, migrations, test generation
- Demands: specification, decomposition, evaluation and system design
The 80% problem — click the bar
What makes up the 20%:
- Edge cases and realistic error handling
- Integration points with other systems
- Subtle correctness requirements
- Wrong assumptions about business logic
- Failure to seek clarification on ambiguous requirements
- Architectural decisions that create invisible maintenance debt
These errors are more insidious because the code "looks right" and may even pass basic tests. The best devs use AI for what it does well and reserve their own attention for what it doesn't — they don't try to be faster by accepting everything.
Coding agents in practice
Three places in your day — and most devs use all three on the same day. The right starting point depends on the task, not on which category sits higher on the autonomy ladder.
Continuous flow
Inline completions, chat that explains/modifies in place, whole-codebase awareness. Where most people first meet AI in coding.
Multi-file with execution
You give a goal in natural language; the agent traverses the codebase, runs tools and tests, and iterates on what it observes. Where serious vibe coding happens today.
Delegate and review later
The agent takes the task and runs autonomously in a cloud sandbox — sometimes for hours — and delivers a pull request as output.
And when the product is an agent?
A support bot, a research assistant, a compliance monitor — these aren't tasks for a coding agent to solve: they're products that need their own persistent memory, scoped permissions, eval coverage and observability. The same terminal workflow that produces prototype scripts now reaches these production agents — the build → evaluate → deploy → observe → refine cycle lives in one place:
🔗 MCP
Model Context Protocol — the standard for tool access across agents and vendors.
🤝 A2A
Agent2Agent — the protocol for delegation between agents. Together, MCP + A2A are the connective tissue of multi-agent systems.
🦀 Real proof
In early 2026, Anthropic's agent teams built a C compiler in Rust in two weeks — humans set direction and reviewed, without writing the implementation.
The economics: CapEx × OpEx in the token era
The conversation usually starts and ends with "how fast can we write code?". For leaders, the critical metric is TCO — and in the AI era, OpEx is dictated by the token economy.
Context as a financial lever + intelligent routing
🧠 Large & expensive models
- Requirements and refinement
- Architecture decisions
- Complex initial implementation
High-complexity tasks — where judgment outweighs costfrontier
routing
⚡ Small & cheap models
- Test generation
- First-pass code review
- CI/CD monitoring
Deterministic, low-complexity tasks — paying premium prices here is wastefast/cheap
Conclusion: Intent as the new Interface
The transition from syntax to intent is not a future prediction — it's a present reality. Developers are already spending more time describing what they want than specifying how to build it. The SDLC is already being compressed, restructured, and reimagined around AI capabilities. The question is not whether this transformation will happen, but how effectively individual developers, teams, and organizations will navigate it.
The framework presented in this paper — the spectrum from vibe coding to agentic engineering, the conductor-to-orchestrator model of developer roles, the taxonomy of ambient, workflow, and autonomous agents, and the factory model of software production — provides a set of mental models for making sense of a rapidly evolving landscape. These models will remain useful even as the specific tools and capabilities evolve.
Three durable principles
🏗 Structure scales, vibes don't
Vibe coding is valid for exploration, prototyping, and personal projects. But for software that organizations depend on, the discipline of agentic engineering — specifications, tests, guardrails, and human oversight of architecture — is not optional. The gap between 'it seems to work' and 'it works correctly under all conditions' is where production outages, security vulnerabilities, and maintenance nightmares live.
🔊 AI amplifies your engineering culture
Organizations with strong testing practices, clear architectural standards, and healthy code review processes get dramatically more value from AI-assisted development than those without. AI is a force multiplier — and it multiplies both your strengths and your weaknesses.
🧠 The human role is evolving, not diminishing
The builders who understand architecture, can define precise specifications, evaluate output critically, and design effective systems of constraints and feedback loops are more valuable than ever. The skills that matter are shifting from implementation to judgment, from writing code to designing the systems that produce code.
We're at the beginning of a transformation that will reshape not just how software is built, but what kind of software is possible to build. Smaller teams will be able to tackle larger problems. Individual developers will be able to build and maintain systems that previously required entire departments. The barrier to creating software will continue to fall, opening the practice of software development to a broader population.
The teams that thrive will be those that embrace AI as a powerful tool while maintaining the engineering discipline that has always been the foundation of reliable software. They'll be the ones who understand that the future of software engineering isn't about choosing between human expertise and AI capability — it's about designing systems where both contribute their unique strengths.
Quiz: test your understanding
8 questions covering the whole guide. No rush — each answer's explanation is part of the study.
Ready-to-copy cheatsheets
Three artifacts you can use today. Click copy and paste into your project.
# AGENTS.md ## Stack TypeScript 6.x · Next.js 16 · Postgres (Drizzle ORM) · Vitest ## Conventions - Pure functions whenever possible; errors via Result<T, E>, never bare throw - Names in English, comments explain "why", not "what" - Every API handler validates input with zod before touching the database ## Hard rules (unbreakable) - NEVER commit secrets; use env vars via .env.local - NEVER install a dependency without confirming with me - NEVER modify migrations already applied in production ## Workflow 1. Read docs/ before implementing 2. Write the test first 3. Run `pnpm test` until green 4. Describe the diff before committing
# REVIEWING AI-GENERATED CODE [ ] Real imports — does each package exist? compatible version? (dependency hallucination is error #1) [ ] Nothing "too clever" — if it looks too clever, be suspicious; code the team doesn't understand = debt [ ] Real error handling — covers realistic failure modes, not just the happy path that passes the test [ ] Business edge cases — the AI doesn't know your refund rule; verify business-logic assumptions [ ] Trajectory, not just output — did the agent RUN the tests or just say it did? check logs / CI hooks [ ] Secrets and permissions — nothing hardcoded; minimal access scope [ ] You could explain this diff — if you can't explain it, don't ship it
# THE NEW SDLC — MIND MAP shift : syntax → intent (you say WHAT, the machine the HOW) spectrum : vibe coding ──────── ai-assisted ──────── agentic eng. divider : verification (tests = deterministic · evals = non-determ.) skill : context engineering (6 types: instructions, knowledge, memory, examples, tools, guardrails) trade-off : static context (always paid) × dynamic (paid on demand) key pattern: Agent Skills — lightweight generalist becomes specialist on demand factory : your output is the SYSTEM that produces code, not the code harness : AGENT = MODEL + HARNESS · agent failures ≈ config failures roles : conductor (real-time) ⇄ orchestrator (async, multi-agent) 80/20 : AI does 80% fast; your value is in the 20% (edge, integration, subtlety) economics : vibe = CapEx↓ OpEx↑↑ · agentic = CapEx↑ OpEx↓ + model routing motto : "Generation is solved. Verification, judgment and direction are the new craft."
Where to start — interactive checklists
Check the boxes as you progress. Progress is saved in your browser.
👩💻 Individual devs
🧭 Engineering leaders
🏢 Organizations
Pocket glossary
Structure scales, vibes don't
Vibe coding is fine for exploration. For software the organization depends on, the discipline of agentic engineering — specs, tests, guardrails, oversight — is not optional. It's in the gap between "it seems to work" and "it works correctly under all conditions" that production failures live.
AI amplifies your engineering culture
Teams with strong tests, clear standards and healthy review extract dramatically more value. AI is a force multiplier — and it multiplies both your strengths and your weaknesses.
The human role is evolving, not diminishing
Those who understand architecture, specify precisely, evaluate critically and design systems of constraint and feedback are more valuable than ever. Skills are migrating from implementation to judgment.
Verification, judgment and direction
are the new craft."
Continue the journey: the companion papers
This guide is Day 1 of a series. The full series has four companions that deepen the themes introduced here — note where to go next.
Agents Whitepaper Series — hub
All series guides in one place.
Agent Tools & Interoperability
The 5 open protocols (MCP, A2A, A2UI, AP2, UCP) that connect agents to tools and to each other.
Context Engineering: Sessions, Skills & Memory
Takes every idea from section 03 of this guide further — deepening the design and management of context at production scale.
Vibe Coding Agent Security and Evaluation
How to protect and evaluate agents: 7 security pillars, 8 evaluation methods and quality gates.
Spec-Driven Production Grade Development in the Age of Vibe Coding
The practices that make the agent workflow production-grade at team scale — from spec to safe deployment.
Resources to continue
The original sources underpinning this guide, for when you want to go beyond the summary.
References (the paper's endnotes)
The numbered footnotes from the original paper, so you can trace each claim to its source.