I Built an AI Content API with 8 Endpoints for $0 - Here's How

I wanted a simple API for AI content tasks that returns clean JSON - not a chatbot, not a complex SDK. So I built ContentCraft AI and listed it on RapidAPI. Here's what it does, how I built it, and what I learned. What It Does ContentCraft AI provides 8 POST endpoints for content creation: Endpoint What it does /rewrite Paraphrase text in 5 tones /seo-analyze SEO score, keyword density, suggestions /headline-generate Headlines in 5 styles /summarize Short/medium/long summaries /email-generate Marketing emails with subject + CTA /social-post Platform-optimized social posts /extract-keywords Keywords with relevance scores /content-improve Grammar, clarity, tone fixes Every response is structured JSON. No markdown, no chat format. Quick Example curl -X POST "https://contentcraft-ai-green.vercel.app/api/v1/rewrite" \ -H "X-RapidAPI-Key: YOUR_KEY" \ -H "Content-Type: application/json" \ -d '{"text": "Your text here", "tone": "professional"}' Response: { "original_length" : 60 , "rewritten_t