Compost or Not: Building an AI-Powered Answer Site
A WordPress site that answers “Can I compost this?” for anything you type — and turns every new question into a searchable page.
Compost or Not is a free, fast answer site for home composters. You type in an item — banana peels, dryer lint, a pizza box, deer poop — and get a clear Yes, No or Sometimes verdict with the reason, how to do it, and what to watch out for. We designed, built and run the site ourselves, and it shows what a WordPress site can do when a custom AI engine, a clean block theme and solid SEO foundations work together.
The idea: one question, answered well
People searching “can I compost ___?” usually land on long articles that bury the answer. We wanted the opposite: the verdict first, in big type, followed by just enough detail to do it right. Because the list of things people might ask about is effectively endless, hand-writing a page for every item wasn’t realistic — so the site writes its own first drafts, in a consistent format, the moment someone asks.
The homepage leads with a single ask box
A custom AI answer engine inside WordPress
The heart of the site is a custom plugin we wrote from scratch. When a visitor asks about an item, WordPress first checks whether that item already has a page. It cleans up the question (“can I put coffee grounds in my compost bin?” becomes “coffee grounds”) and matches plural and singular forms, so repeat questions go straight to the existing answer without any AI call at all.
For anything new, the plugin asks Google’s Gemini models for an answer using structured output: instead of free-form text, the model has to return a strict JSON schema — verdict, short answer, why, how-to steps, watch-outs, breakdown time, green/brown material type, alternatives, category, FAQs and a meta description. That keeps every page in exactly the same shape and makes the answers easy to check.
- Model racing: the request goes to several models in parallel, the first valid answer wins, and the slower requests are cancelled — so answers come back quickly even when one model is slow.
- Guardrails: the prompt rejects gibberish, offensive input and prompt-injection attempts, and a low temperature keeps answers factual and consistent.
- Rate limits: per-visitor hourly limits and a daily cap protect the site and the API budget.
- Quality gate: new answers are saved as drafts and only publish automatically once a second person asks the same question, so one-off or joke queries never become public pages.
- Admin tools: a settings screen with a “Test connection” check, plus a log of every AI request for troubleshooting.
A content model built for answers
Every answer is its own “compost item” — a custom post type with a clean /can-i-compost/ URL, organized into categories such as Food Scraps, Yard & Garden, Pet & Animal, Paper & Cardboard, Textiles and Household. The verdict, FAQs and sources are stored as structured data, which drives both the page design and the search-engine markup. Because answers are ordinary WordPress posts, they can be reviewed and edited like any other page — and they are. We proofread generated answers and correct anything that’s off, such as moving deer droppings from “Yes” to “Sometimes” because of pathogen risk.
An answer page: verdict first, then the details
The A–Z index of every answered item
Design: verdict first, no clutter
The site runs on WordPress’s modern block theme system (Twenty Twenty-Five) with a custom stylesheet layered on top. We designed a simple logo — a leaf with a check mark growing from a soil mound — and built the palette around it: deep forest green, a brighter leaf green and a soft sage background.
- Color-coded verdict cards (Yes, Sometimes, No) so the answer reads at a glance
- Quick-fact chips for breakdown time and green/brown material type
- Consistent sections on every page: Why, How to compost it (or how to get rid of it), Watch out for, What to do instead, and FAQs
- Mobile-first layouts, and an A–Z index plus category pages for browsing
Photography for every page
A text-only answer site feels thin, so every item page gets its own realistic photo — generated with AI image tools in a single editorial home-and-garden style, then reviewed one by one. We deliberately varied the compositions (overhead flat-lays, kitchen counters, garden beds, compost piles) so the site doesn’t repeat the same shot. Images are compressed to WebP and double as each page’s featured image for search and social sharing. The homepage “Recently answered” feed only shows items that have a photo, so new pages don’t appear there until they’re finished.
“Recently answered” cards with verdict badges
SEO built in from day one
- Search-friendly titles generated from the verdict, e.g. “Can You Compost Banana Peels? Yes, Here’s How”
- FAQ and breadcrumb structured data on every answer page, built from the stored FAQs
- Rank Math for XML sitemaps and meta descriptions, with schema output cleaned up to avoid duplicates
- Verified in Google Search Console and Bing Webmaster Tools, with the sitemap submitted to both
Gear guides and affiliate tools
To support the site, we added a hub of buying guides — Compost Tumbler vs. Bin, Best Bokashi Composting Kits, Best Countertop Compost Bins and Best Compost Bins for Beginners. A small affiliate module adds product boxes and “our picks” blocks through shortcodes, and can suggest relevant gear on answer pages based on the verdict and category.
The gear guides hub
Hosting, speed and email
The site is hosted on SiteGround with Cloudflare DNS, uses lightweight WebP images throughout, and has SPF and DMARC records set up so site email is delivered reliably. A clear note in the footer explains that answers are AI-assisted.
What we built
- Custom WordPress plugin: AI answer engine with structured output, parallel model racing, rate limiting and a draft-then-publish quality gate
- Custom post type and categories for compost items, with structured verdict, FAQ and source data
- Block theme customization: logo, color palette, verdict cards and page templates
- An AI photo workflow with a consistent style and WebP compression
- Technical SEO: verdict-based titles, FAQ and breadcrumb schema, sitemaps, Search Console and Bing setup
- Gear guides and a shortcode-based affiliate module
- Hosting, Cloudflare DNS and email authentication (SPF/DMARC)