A developer's year-long journey reveals the critical prompts for edge cases, error states, and integrations that turn a 48-hour Claude Code MVP into a shippable product.

From Vibe Code to Viable Product: The 6 Claude Code Prompts You're Missing

After a year of shipping products built with Claude, developer Sankalp has identified the precise gap between a "working" prototype and a trustworthy product. The insight is crucial for anyone using Claude Code: the AI excels at building the happy path, but the human must prompt for everything else.

The Gap: From Working Code to Trustworthy Product

You can get a functional MVP from Claude Code in 48 hours. The frontend renders, the API calls work locally, and the core logic executes. This is "vibe coding." The trap is believing this is a finished product. The real work—and where your product thinking becomes essential—is in handling all the scenarios Claude won't anticipate unless you explicitly ask.

Your job is no longer writing the core logic. It's systematically prompting for the gaps.

The 6 Prompt Categories You Must Cover

Here are the specific areas where you need to direct Claude Code after the initial build. These aren't vague concepts; they are direct prompts you should be running.

1. Prompt for Empty States

Don't: Assume users arrive with data.
Do: Design the first screen a new user sees.

Claude, review the `Dashboard.jsx` component. Generate a new version that includes a comprehensive empty state for a first-time user. It should:
1. Display a welcoming illustration.
2. Clearly state what the product does.
3. Provide one primary, obvious button for the first action (e.g., "Create Your First Project").
4. Include a short, helpful hint text.
Write the JSX and CSS for this state and integrate it with the existing conditional logic.

2. Prompt for Error States & Silent Failures

Don't: Let API failures or invalid inputs fail silently in the UI.
Do: Build the failure path before you polish the success path.

Claude, analyze the `submitPayment` function in `paymentService.js`. For each possible failure point (network timeout, 4xx/5xx API response, invalid card format), write a corresponding user-facing error message. Then, modify the frontend `PaymentForm.js` to display these errors contextually and clearly, ensuring no failure is silent. Provide a fallback UI if the error service itself fails.

3. Prompt for Edge Cases Explicitly

Claude builds for the ideal input. You must define the boundaries.

Claude, for the `UserProfile` form, list all possible edge cases for the 'bio' text field (empty string, 1000+ characters, profanity filter, emoji-only, SQL injection attempt). Now, write the validation logic and UI feedback for each case. Integrate this into the existing form handler.

4. Prompt for Integration Testing on Live URLs

What works on localhost will break in production. Prompt Claude to help you test realistically.

Claude, write a comprehensive test script for our Stripe webhook integration. The script should:
1. Use `ngrok` to expose my local server.
2. Update the Stripe dashboard webhook URL.
3. Trigger test events (payment.succeeded, payment.failed, customer.subscription.deleted).
4. Verify the events are logged and processed correctly in our database.
Provide the shell commands and the Node.js script.

5. Prompt for the "Stranger" Mental Model

You cannot see your own UX blind spots. While you can't fully automate user testing, you can prompt Claude to simulate it.

Claude, act as a first-time user who has never seen this SaaS dashboard before. Go through the README and the main `App.jsx` component. List every step, button, or piece of terminology where you, as a novice, would hesitate or be confused. For each, suggest a clearer label, tooltip, or onboarding step.

6. Prompt for the Paywall Readiness Audit

Before adding payments, conduct a final audit through Claude.

Claude, review the entire codebase. Generate a checklist for paywall readiness. For each core user flow (signup, create project, export data, delete account), identify any point where a user could get stuck due to an unhandled error, missing feedback, or unclear instruction. Output as a markdown checklist I can manually verify.

Integrating This Into Your Claude Code Workflow

This isn't a one-time phase. Integrate these prompts into your development cycle:

1. After Happy Path: Once the core feature works, immediately run the Error States and Edge Cases prompts.
2. Before UI Polish: Run the Empty States and "Stranger" Mental Model prompts before finalizing styles.
3. Pre-Deployment: Run the Integration Testing prompt for any third-party service (auth, payments, email).
4. Pre-Monetization: Run the Paywall Readiness Audit prompt.

Create a CLAUDE.md file in your project with a section titled "Product Gaps" containing these prompt templates. This systematizes the transition from vibe code to viable product.

The 48-hour build gets you to the starting line. These prompts are the race.

Originally published on gentic.news