# How to Vibe Code Your Own ProWritingAid (and Stop Paying for It)

> The Storyteller's Toolkit

- Site: https://prowritingaid.com
- Category: Writing Assistant & AI SaaS
- Platforms: Web app, Browser extension
- Verdict: **Solid side project** (64/100 vibecodeable)
- Estimated effort: 3-4 weeks of part-time work

## Verdict

Build a personal single-user web editor clone with AI-powered reporting and rephrasing, but skip the native desktop extensions and offline integrations.

ProWritingAid combines heavy-duty grammar checking, custom statistical analysis rules (like sentence variety and sticky sentences), and modern LLM calls for structural critiques. While you can easily replicate the LLM wrapper parts (Sparks, Chapter Critiques, and Rephrases) using Next.js and the Vercel AI SDK, writing fast, deterministic algorithms for 25+ stylistic reports requires significant linguistic and regex parsing effort. Furthermore, building native add-ins for Microsoft Word, Google Docs, and Scrivener is a punishing engineering task for a solo builder. For personal use, building a dedicated web-based markdown and rich-text editing suite that hooks into custom analysis endpoints is a rewarding challenge.

### What you can't replicate

- Native integrations with Microsoft Word, Google Docs, and Scrivener out-of-the-box
- The exact proprietary database of author comparisons across 90 fiction writers
- Enterprise compliance arrangements and multi-platform desktop shell wrappers (Desktop Everywhere)

## What it does

AI-powered writing assistant and deep manuscript editing platform for novelists, students, and fiction writers offering analytical reports, brainstorming tools, and rephrasing.

### Core features

- Real-time grammar, spelling, and style checking
- 25+ analytical reports (clichés, pacing, overused words, readability)
- Sparks (AI rewriting, text expansion, and idea generation)
- Chapter Critique and Manuscript Analysis
- Story Canvas (structured plotting and guided brainstorming)
- Rephrase tool with tone and length adjustments

## The business

### Pricing

- Free: Free — Basic writing suggestions and strict daily limits for casual users.
- Premium (Monthly): $30.00/mo — Unlimited word count and writing reports for individual authors.
- Premium Pro (Monthly): $36.00/mo — Expanded AI limits, live workshops, and co-writing sessions.

### Funding

$0 raised.

Founded 2012.
Team size: 51-100.

## The hard parts

- Writing deterministic, non-LLM style parsers for stylistic rules (clichés, sticky sentences, sentence length variety) without relying solely on probabilistic LLMs
- Large-document token management and chunking for 300,000-word manuscript structural analyses without breaking context windows or hitting rate limits
- Building robust browser extensions and rich text editor overlays that inject highlighting underlines smoothly without lagging large documents
- Ensuring zero data retention and strict privacy guarantees for authors' unpublished manuscripts

## How to vibe code ProWritingAid

### Prerequisites

- Node.js (free): Required runtime for building and running the full-stack web application.
- GitHub (free): Version control and deployment pipeline management.
- Anthropic API Key (pay-as-you-go): Powers advanced LLM calls for Sparks, Chapter Critiques, and manuscript insights.

### Recommended AI tools

- Cursor: Primary AI code editor for rapidly scaffolding UI components and managing multi-file edits.
- Claude Code: Terminal-based coding agent for handling complex backend logic, database schema design, and script integrations.

### Stack

- Frontend: Next.js
- Backend: Next.js Server Actions
- Database: Turso
- Auth: better-auth
- Payments: none
- Other: Vercel AI SDK, Tailwind CSS, TipTap Editor

### Hosting

- Vercel (Hosting the Next.js frontend and serverless API endpoints): $0/mo (Hobby tier)
- Turso (Storing user documents, outlines, and chapter drafts as edge SQLite databases): $0/mo (Free tier)

### Build guide

1. **Project Scaffolding & Editor Setup** — Initialize the Next.js application with Tailwind CSS, configure better-auth for single-user or local authentication, and integrate TipTap or a similar rich-text editor to serve as the core writing canvas interface.

```
Initialize a new Next.js project with Tailwind CSS and TypeScript. Set up better-auth with email/password authentication backed by a Turso SQLite database using libSQL. Create a clean writing dashboard layout with a sidebar navigation for 'Documents', 'Story Canvas', and 'Reports'. Integrate the TipTap rich-text editor in the main workspace with a custom floating toolbar for word count tracking, document type settings, and undo/redo operations. Ensure clean styling matching a professional writing software aesthetic.
```

2. **Document Management & Storage** — Build out the document creation, auto-saving, and file retrieval systems so writers can manage multiple chapters or manuscripts seamlessly.

```
Implement a robust document management system in Next.js using server actions and Turso database. Create tables for documents (id, title, content, word_count, created_at, updated_at). Add auto-saving functionality to the TipTap editor that triggers debounced API updates every 2 seconds. Build a document list view with sorting, renaming, and deletion capabilities, ensuring smooth state transitions and loading indicators.
```

3. **Deterministic Writing Style & Statistics Engine** — Develop client-side or server-side parser utilities that compute basic style metrics: sentence length variation, paragraph length, passive voice detection via regex patterns, and overused word frequency counters.

```
Write a utility module in TypeScript that analyzes plain text extracted from the editor. Implement algorithms to calculate average sentence length, identify passive voice verbs using regex patterns, flag overly long sentences, and count word frequencies to highlight overused words. Display these metrics in a dedicated 'Summary Report' sidebar tab with clickable highlights in the editor canvas.
```

4. **AI Writing Assistant & Sparks Integration** — Integrate the Vercel AI SDK with Anthropic's Claude API to handle sentence rephrasing, tone adjustments, text expansions, and generative writing sparks.

```
Set up the Vercel AI SDK in Next.js connecting to the Anthropic API. Create backend API routes for 'Rephrase' (accepting a sentence and target tone like formal, shorter, or sensory) and 'Sparks' (accepting prompt instructions to expand, summarize, or continue drafting). Build clean UI modal components in the editor that allow users to select text, request an AI modification via a floating menu, and review diffs before applying changes to the editor content.
```

5. **Chapter & Manuscript Critique Pipelines** — Build automated LLM evaluation workflows that take entire chapters or uploaded manuscript text and output structured developmental critiques, plot pacing notes, and beta reader perspectives.

```
Implement an asynchronous analysis workflow using Next.js server actions and Anthropic API with streaming support. Create a 'Chapter Critique' feature that splits text into manageable chunks if needed, passes it through a structured prompt designed for developmental fiction editing, and renders a comprehensive report breaking down pacing, character voice, tension, and actionable revision suggestions into clean card components.
```

6. **Story Canvas & Planning Tools** — Create a guided brainstorming and outlining interface (Story Canvas) where writers answer prompts about characters, setting, and plot arcs to generate instant idea feedback reports.

```
Build a 'Story Canvas' planning interface featuring structured input forms for core story elements: protagonist, setting, central conflict, stakes, and theme. Implement an 'Idea Feedback Report' generator that bundles these inputs into a structured prompt sent to Claude, returning categorized insights highlighting story strengths, developmental gaps, and next drafting steps displayed in an interactive dashboard.
```

### Cost vs paying

**Starting costs (one-time):**

- Domain name (optional): $12.00 one-time
- Anthropic API starting credits: $15.00 one-time
- Total: ~$27.00 one-time

**Ongoing costs (monthly):**

- Anthropic API usage for Sparks & Critiques: ~$5.00/mo
- Vercel & Turso hosting: $0.00/mo
- Total: ~$5.00/mo

- Paying for the SaaS instead: $30.00/mo
- Build time: 35 hours
- AI tool credits: $20.00 (Cursor Pro)
- Break-even: 1 month

## Sources

- [ProWritingAid Official Website & Feature Pages](https://prowritingaid.com)
- [ProWritingAid Pricing Page](https://prowritingaid.com/pricing)
- [Tracxn Company Profile - ProWritingAid](https://tracxn.com)
- [The Creative Penn Interview with Founder Chris Banks](https://www.thecreativepenn.com)