Methodology

How GoCodebook works

Every answer on GoCodebook should be checkable against the law it came from. This page explains where our text comes from, how the AI layers are grounded in it, and what the dates and status labels on each page mean.

Where the code text comes from

The foundation is the Code Library: the verbatim enacted text of 600 California codes and ordinances — municipal zoning codes for 540 cities and counties, the California Building Standards Code (Title 24, 2025 edition), and the statewide housing statutes. Text is ingested from each jurisdiction's officially published code (the same publishers cities themselves link to), preserving the original title/chapter/section structure — 256,000+ sections — so every citation resolves to a stable, readable location. We do not paraphrase this tier: it is the enacted text.

How AI answers are grounded

When you ask a question, the assistant retrieves from the actual code text for the relevant jurisdiction — not from general internet knowledge — and answers with citations to the controlling sections. Citations link into the Code Library so you can read the verbatim section yourself. If the code doesn't address something, the honest answer is that it doesn't, not a guess.

How the written guides are produced

The per-city topic guides (for example, a city's parking or ADU standards) are AI-generated drafts grounded in that specific city's code text, with the retrieved source passages listed at the bottom of each page — you can expand them to compare the guide against the ordinance language it was drawn from. Each guide shows a Last reviewed date. ADU pages work from a two-part model: the California state-law baseline that applies everywhere, plus the city's local ordinance where it goes beyond state law; a "verified" status means the page has been checked against that city's published ordinance, while "state defaults" means the state baseline is shown pending local verification.

Freshness

Codes change. Documents are re-ingested as jurisdictions publish updates, and the review/verification dates you see on guide and ADU pages reflect when that page's content was last checked — we surface the dates precisely so you can judge staleness for yourself.

Corrections

If you find an error — a wrong citation, an outdated standard, a misread ordinance — tell us. Reports go to the team directly, and corrections ship with the next content update to the affected page.

Limitations

GoCodebook is general information, not legal advice, and no page here replaces the judgment of your local planning and building departments — they are the final authority on how a rule applies to a specific parcel. Verify the controlling requirement with the jurisdiction before you rely on it.