Where the answers come from
Plainly: how rules get into WhatSignFits, what is checked, and what is not.
1. Official sources only
Every rule comes from a public, official document published by the city: its sign code, a sign-type handout, a fee schedule or a permit submittal guide. We save a dated copy of each document, so we can tell when the city changes it. No private portals, no paid databases.
2. Rules are extracted by AI
Rules are extracted from those documents by AI (large language models). Each rule is one fact, for example the maximum area of a wall sign in one zoning district, together with the section number and a word-for-word quote from the document.
The lookup itself does not use AI: when you search, it reads stored rules. Nothing is generated while you wait.
3. Automatic checks
Before a rule is shown as a figure, it has to be confirmed by AI. Two separate AI readings of the city's text must find the same rule, or, if only one reading found it, a separate AI check is shown just the quoted words and the text around them and must confirm that they state that rule for that sign type and district. Automatic checks then have to pass as well:
- The quote matches word for word. The quoted text must appear exactly in the saved copy of the city's document.
- The number is in the quote. A figure such as "200 sq ft" must appear in the quoted text itself.
- Common-sense checks. The unit fits the item (feet for height, square feet for area) and the value is within a plausible range.
Anything that fails is shown as "Not confirmed. Check with the city.", with a link to the city's sign office, and no figure.
4. What is not done
- No person reviews each rule. The AI checks and the automatic checks above all run without a person. They catch invented quotes and misread numbers, but they cannot catch every misunderstanding of how a rule applies.
- Planned developments, master sign plans (sign coordination plans, comprehensive sign packages) and special sign districts are not covered. Where we know an address may be affected, the result warns you.
- Some cities do not publish a zoning map we can read. There you pick the zoning district yourself.
5. Keeping up with changes
We fetch the source documents again and compare them with the saved copy. When a city has changed a document, the change is flagged and the affected rules are extracted and checked again. Some city websites block automated access; those documents are saved by hand. Each line in a result shows the date its source was last checked.
6. What you should do
Use the result to quote and plan the job, then check the linked section before you file. The city has the final say. If something is wrong, use Report an error.