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A Practical Guide to AI Prototyping

November 17, 2025

Written By Alice Moore

You’ve probably tried a few AI app builders by now. They work great for demos, but… well, if demos are the coffee chugging, rewrites to functional apps are the crashout.

This guide is about AI prototyping that survives handoff: working UI, real data, and a path to a clean pull request.

What is AI prototyping?

AI prototyping is not a replacement for wireframes. It goes further by giving teams clickable flows, basic logic, and real data so they can validate decisions faster than static diagrams allow. Ideally, AI prototyping means getting work done that you don’t have to throw away later.

Practically, that looks like:

  • AI‑assisted scaffolding that uses your components and design tokens
  • Realistic UI states (loading, error, empty) and small pieces of business logic
  • Real or representative data to exercise the flow
  • Outputs that live in your repo as diffs engineers can review

What follows is a production‑minded walkthrough: when to use AI prototyping, where popular tools help or hurt, and how to keep code mergeable.

AI prototyping tools are systems that turn prompts or design inputs into working UI, logic, and data-connected flows. They help teams test ideas quickly without manual setup.

Most AI prototyping tools let PMs and designers build usable flows without writing code, though developers still refine and merge the outcomes.

These tools cluster into a handful of categories, each with clear strengths and tradeoffs. Here’s a quick map to see where they fit and what to watch for as you move from demo to mergeable code.

ToolCategoryPersona fitVisual editingStack targetsRepo/PR flowNotable gotchas

Lovable

AI app builder/copilot

Non‑devs, PM

Present (less capable than v0)

React‑first full‑stack

Export/sync to GitHub; PRs vary

Can over‑engineer; repair loops

v0

AI app builder/copilot

PM, Dev

Basic CSS design mode

React/Next (shadcn/Tailwind)

GitHub import; dev integrates PRs

Editor limits; shadcn‑first

Bolt.new

AI app builder/copilot

PM, Dev

None (no real CSS design mode)

Multiple JS frameworks (WebContainers)

GitHub link; hosted preview; manual merges

Generic patterns; extraction friction

Builder.io Fusion

Repo‑native visual + code

Product teams (PMs, Devs, Designers)

Robust visual + agent

Multi‑stack

Repo/PR‑first

Requires optional repo/design setup for PR flows

Replit Agent

Cloud IDE with agent

Dev

None

Many languages

Imports repos (incl. Bolt/Lovable); PRs on GitHub

Learning curve; sandboxed

Firebase Studio

Cloud IDE with agent (adjacent)

Dev

None

Multi‑framework via Firebase/GCP

Imports repos/templates; PR flow varies

Firebase‑opinionated

Figma Make

Design‑to‑code

Designer

Full Figma

HTML/CSS/React variants

Export → manual integration

Code semantics; a11y/perf gaps

Locofy

Design‑to‑code

Designer

Figma plugin

React/HTML/CSS (common targets)

Export → manual integration

Code quality; runtime coupling

Anima

Design‑to‑code

Designer

Figma plugin

React/HTML/CSS (common targets)

Export → manual integration

Code quality; a11y/perf gaps

Tool Lovable
Category AI app builder/copilot
Persona fit Non‑devs, PM
Visual editing Present (less capable than v0)
Stack targets React‑first full‑stack
Repo/PR flow Export/sync to GitHub; PRs vary
Notable gotchas Can over‑engineer; repair loops
Tool v0
Category AI app builder/copilot
Persona fit PM, Dev
Visual editing Basic CSS design mode
Stack targets React/Next (shadcn/Tailwind)
Repo/PR flow GitHub import; dev integrates PRs
Notable gotchas Editor limits; shadcn‑first
Tool Bolt.new
Category AI app builder/copilot
Persona fit PM, Dev
Visual editing None (no real CSS design mode)
Stack targets Multiple JS frameworks (WebContainers)
Repo/PR flow GitHub link; hosted preview; manual merges
Notable gotchas Generic patterns; extraction friction
Tool Builder.io Fusion
Category Repo‑native visual + code
Persona fit Product teams (PMs, Devs, Designers)
Visual editing Robust visual + agent
Stack targets Multi‑stack
Repo/PR flow Repo/PR‑first
Notable gotchas Requires optional repo/design setup for PR flows
Tool Replit Agent
Category Cloud IDE with agent
Persona fit Dev
Visual editing None
Stack targets Many languages
Repo/PR flow Imports repos (incl. Bolt/Lovable); PRs on GitHub
Notable gotchas Learning curve; sandboxed
Tool Firebase Studio
Category Cloud IDE with agent (adjacent)
Persona fit Dev
Visual editing None
Stack targets Multi‑framework via Firebase/GCP
Repo/PR flow Imports repos/templates; PR flow varies
Notable gotchas Firebase‑opinionated
Tool Figma Make
Category Design‑to‑code
Persona fit Designer
Visual editing Full Figma
Stack targets HTML/CSS/React variants
Repo/PR flow Export → manual integration
Notable gotchas Code semantics; a11y/perf gaps
Tool Locofy
Category Design‑to‑code
Persona fit Designer
Visual editing Figma plugin
Stack targets React/HTML/CSS (common targets)
Repo/PR flow Export → manual integration
Notable gotchas Code quality; runtime coupling
Tool Anima
Category Design‑to‑code
Persona fit Designer
Visual editing Figma plugin
Stack targets React/HTML/CSS (common targets)
Repo/PR flow Export → manual integration
Notable gotchas Code quality; a11y/perf gaps

Below, we’ll go into a bit more detail.

Figma‑first tools like Figma Make, Locofy, or Anima prioritize speed for designers. You hand them a frame, and they hand you code that looks convincingly close to the mock. For early concepting, pixel‑fidelity explorations, or stakeholder walk‑throughs, they offer a fast way to get something on screen without pulling an engineer off sprint work.

The tradeoff is in the handoff. Exports often target a narrow set of outputs (typically HTML/CSS/React variants) and can couple to tool‑specific runtimes. That’s where code semantics, accessibility, and performance regressions sneak in.

Plus, if your team maintains any sort of design system, expect lots of time to re‑map tokens and prune one‑off utility classes before code is close to merge‑ready.

Tools like v0, Bolt.new, and Lovable turn prompts into working apps with hosted previews. They shine for PM/founder zero‑to‑demo, simple CRUD, marketing flows, and UI spikes where speed beats fidelity. You get good defaults, a quick preview link, and enough interactivity to validate a direction with minimal setup.

Compared to other prototyping tools, AI app builders are fastest for simple demos but struggle with real-world constraints like data handling, structure, and merge-ready code.

They struggle when it comes to shallow data connectors, editor limits, and vendor lock‑in. Exports need refactored to match your codebase lints, types, and directory structure.

And the tools have their own differences:

  • v0 leans shadcn/Tailwind with a basic visual CSS mode.
  • Lovable blends visual editing with code and can jump from Figma (via Builder.io’s agent) to a simplified GitHub export.
  • Bolt.new is a tad bit closer to an IDE, offering multiple JS frameworks via WebContainers.

Each tool has a free tier, so you can suss out the features for yourself.

Cloud IDEs like Replit Agent and Firebase Studio add AI copilots to full IDE environments, meaning they work like online versions of popular tools like Cursor and Windsurf. They’re great when you want to stay close to the metal and keep tight control over dependencies and CI.

But that said, Cloud IDE agents are usually a better fit for developers who code daily rather than PMs or designers who need fast, visual prototyping. They have a much steeper learning curve than the other tools and more setup overhead.

These tools do import GitHub repos and often give you the ability to open PRs on GitHub, but they feel more sandboxed than repo‑native PR flows, which can make integrating with your engineering team tricky.

A tool like Builder.io’s Fusion brings a visual editor and AI agent directly into your repo. It’s multi-stack and repo/PR-first, so the prototype you click through already lives in your codebase and can be reviewed like any other change.

The upside of Fusion is that it’s a visual IDE, which makes it really easy for anyone on your team—designer, PM, developer—to jump in and work from the exact same source of truth while prototyping.

Diagram comparing old handoff workflows with a Visual IDE. The left side shows a slow sequence from PRD to static designs to code rebuilds leading to late feedback. The right side shows a faster loop where a branch is opened, real screens are edited directly, a PR is sent, tests run, and changes merge quickly.

Also, thanks to Builder’s long history of making Figma-to-code tooling, Fusion offers a reliable round-trip workflow for designers who want to keep using Figma.

The only real downside is that, as a tool focused on visual building and AI agents, it offers less for developers who just want to jump into code. However, since it runs as a VS Code extension, developers can still use the tools they love right alongside it.

Now that you know the landscape, here’s where AI prototyping really shines. Use them where speed buys clarity—testing ideas with stakeholders, shaking out copy and information architecture, and pressure‑testing tricky interactions—before you borrow from design and engineering budgets.

Diagram comparing traditional product workflows to AI prototyping. The top shows a long path from idea to PRD to design to engineering before validating the idea, which creates wasted cycles. The bottom shows a faster loop where ideas move into AI prototyping, then validation, then design and engineering, with quick feedback early in the process.

Here are some of the best places to use AI prototyping.

When a product requirements document (PRD) is still in flux, turn the riskiest parts into clickable flows within an hour or so. Stakeholders react to working screens, not bulleted specs, and you’ll get clearer alignment on scope and ideal customer profiles.

A realistic demo also unlocks budget conversations earlier because you’re showing value, not just promising it.

Instead of debating copy or information architecture in a doc, generate a few variants and put them in front of users. Use lightweight analytics or brief surveys to capture directional data: which navigation label reduces time to task, which headline improves comprehension, which flow gets abandoned.

You’re not chasing statistical significance. You’re just avoiding obvious mistakes before they become rewrites.

Complex interactions, such as pagination with caching, optimistic updates, or multi‑step forms, benefit from prototyping in realistic conditions.

Specify concrete scenarios and expected outcomes, include state handling (loading, error, empty), and add microinteractions. You’ll surface feasibility issues early and trim risk before allocating full engineering capacity.

Regardless of what you’re using AI prototyping for, it’s important to prevent throwaway work that wastes design and development cycles. Ideally, your prototypes should be able to be quickly and directly upgraded to production-grade code.

To make that possible, treat AI as a collaborator inside your existing rails, and not a shortcut around them. The best tools mirror your team’s real environment: they understand your design system, your component library, and your review culture.

When evaluating tools, look for ones that preserve your code as your source of truth instead of reinventing it—tools that write code your engineers would actually merge, and visuals your designers recognize.

Consistency, not novelty, is what turns prototypes into progress. This is what separates real AI prototyping from one-off demos that look good but never make it into production.

Then, define what “mergeable” means for your team. Are you optimizing for iteration speed, design accuracy, or data realism? Set those expectations early so everyone, from PM to designer to engineer, knows when an experiment is done versus when it’s ready for code review.

Good AI workflows don’t erase human checkpoints; they make those checkpoints happen sooner, with clearer context and fewer surprises.

AI helps designers move faster, but it cannot replace design judgment. Teams still need designers to shape interaction patterns, visual clarity, and usability while AI handles scaffolding and routine translation work.

Great prompting is more about sharing context than clever phrasing.

Teams that treat AI like a junior teammate instead of a vending machine get the most from it. The goal is to teach your tools to reason inside your team’s boundaries: your design language, your product values, and your definition of “done.”

Think of prompting less as an instruction and more as a loop of intent, feedback, and refinement across product, design, and engineering. The most successful teams use AI to extend their culture of clarity instead of shortcutting it.

Use these principles to guide how you evaluate and collaborate with AI tools:

  • Start with your system. Ground the AI in your team’s real components, tokens, and patterns. If a tool can’t learn your rails, it can’t produce work your team will keep.
  • Communicate visually. AI understands structure better than style. Anchor its context in real screens, flows, or examples. The more tangible your references, the closer you’ll get to usable outcomes.
  • Prototype for realism, not perfection. A believable interaction, with real data and states, reveals more truth than a polished fake. Treat early prototypes like experiments, not marketing assets.
  • Optimize for mergeable outcomes. Choose tools that create small, transparent changes your team can reason about instead of flashy demos with thousands of lines of code. Mergeability is the real, if unsexy, measure of progress.
  • Keep humans in the decision loop. Use AI to explore possibilities and surface insights, but let humans set standards and make trade-offs. A good workflow automates the rote, not the judgment.
  • Measure clarity, not cleverness. Track how quickly your team can move from idea → prototype → confident next step. Speed to shared understanding matters more than the size of the output.

Even with good habits and clear principles, most tools still fail to meet teams where they actually work.

The problem isn’t that they can’t generate code; it’s that they can’t generate alignment.

When prototypes drift from the systems they are meant to reflect, teams spend more time rebuilding than learning.

Many tools promise instant fidelity, but if they don’t understand your components or tokens, they improvise. The result looks right until you examine it closer: mismatched buttons, off-scale spacing, and code no one wants to own.

Each small inconsistency adds friction. Designers chase visual fixes, engineers refactor, and product momentum slows.

A prototype has no lasting value if it can’t merge cleanly into your team’s repository. When AI exports ignore structure, testing, or readability, the experiment becomes a dead end instead of a foundation.

Teams lose the chance to treat prototypes as living experiments inside their workflow, and the rebuild tax arrives on schedule.

Without real data, everything looks better than it is.

Tools that rely on placeholders hide the messy realities of latency, authentication, and error states—the details that decide whether a product feels fast or broken. PMs make decisions on idealized demos and discover the trade-offs too late.

Lock-in, missing test hooks, and brittle authentication flows rarely appear in marketing videos, yet they determine whether a tool fits into your ecosystem or sits on the sidelines.

A prototype that can’t coexist with your codebase, governance, and analytics isn’t a shortcut; it’s another silo.

The good news is that these gaps aren’t inevitable. Fusion closes them by bringing AI prototyping into the same environment where your team already designs, reviews, and ships, creating a faster, cleaner path from idea to pull request.

Diagram contrasting linear handoffs between PM, designer, and developer with a collaborative model. The top shows a PM handing off to a designer, then to a developer, then shipping. The bottom shows PMs, designers, and developers working together inside a shared Visual IDE, leading straight to shipping.

Fusion’s approach centers on three principles:

Fusion connects to your existing repository and thoroughly indexes your design system, so prototypes speak the same visual and technical language as your product.

Teams see familiar components, tokens, and structure from the start, which means fewer rewrites and cleaner reviews.

Instead of generating static mockups, Fusion can immediately use your team’s existing data. It can also import Figma frames and translate them to code that matches your design system.

That makes prototypes behave like real software early in the process and helps PMs validate flows, edge cases, and latency before engineers commit cycles.

Fusion offers a full visual canvas that sits on top of your code and design system. Rather than switching between Figma or a mock tool and your repository, PMs and designers can preview, tweak, and align layouts in the same system your engineers use.

This visual layer lets non-dev stakeholders participate meaningfully in prototyping without sacrificing technical realism.

Each prototype lives as a small, reviewable change inside your repo. Linters, type checks, and CI run as usual, so the jump from “prototype” to “production” feels like a normal iteration rather than a rebuild.

The outcome is a faster loop between ideas and shipped value.

If you’re ready to test the workflow, start small. Choose one page or flow and generate a prototype inside your real repo. Use your components, your data, and your normal review process. That’s where Fusion shines.

You’ll see the difference immediately: cleaner diffs, faster reviews, and a shorter path from concept to commit.

Prototype smarter, not just faster. Start with tools that fit your team’s stack and process. You’ll save time now and avoid the rebuild tax later.

Try Fusion free or watch this quick demo to see repo-native prototyping in action:

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