How we verify city solar permit data

For our flagship cities — currently Phoenix, Los Angeles, San Diego, Denver, Orlando, and Austin — a human curator reads the city's official permitting page, solar checklist PDF, and fee schedule, then enters codes, setbacks, fees, and turnaround times by hand. Each curated city ships with a list ofseed URLs (the canonical .gov sources) attached to the record.

For every other city we cover, an AI verifier runs the same workflow at scale: scrape the official permitting pages with Firecrawl, then ask Google Gemini to extract only the facts present in the source material — never to guess. The model returns a confidence score per city. Anything below 0.5 stays marked as a stub until a curator reviews it.

Published cities are re-audited weekly; AI-verified cities monthly. Each audit re-scrapes the seed URLs and diffs the result against what's on the page. If anything has changed, the city is flagged in the admin queue for review before the public page updates. The last-verified date is shown on every city page.

Every city page has a Report an error button. Installers who actually pull permits in that jurisdiction can flag wrong fees, outdated setbacks, or missing documents — with an evidence URL when possible. Corrections are reviewed and incorporated, and contributors are credited on the city page they help.