Authentication & rate limits

Every endpoint works without a key, and every tier reads the same scans, Italian and English. A key raises your rate limit; a Patron or Developer key also adds the Patron languages (French, German, Spanish) to folio responses, under enrichment.translations.

Tiers

Tier	Limit	How
Anonymous	60 requests / hour per IP	Just call the API
Free key	1,000 requests / day	Sign in on /developers — the key appears instantly
Patron key	10,000 requests / day	Included with a Patron membership ($40 / year)
Developer key	100,000 requests / day	The Developer plan ($99 / year) — every Patron benefit too

Your key follows your membership: it moves to the higher tier the moment you become a Patron or Developer, with no new key to copy. Rotate it on /developers if it leaks — the old one stops working at once.

Using a key

Pass it in the X-API-Key header:

curl "https://venivididavinci.com/api/v1/search?q=anatomy" \
  -H "X-API-Key: your-key-here"

Reading your limits

Every response carries your current window:

X-RateLimit-Limit: 60
X-RateLimit-Remaining: 41
X-RateLimit-Reset: 1784418134
X-RateLimit-Tier: anonymous

X-RateLimit-Reset is a Unix timestamp — when your window starts over. When you exceed the limit you get a 429:

{
  "error": {
    "code": "rate_limited",
    "message": "Anonymous limit is 60 requests/hour. Get a free key at https://venivididavinci.com/developers and pass it as X-API-Key."
  }
}

Library data is served with long CDN cache headers. If you request the same URLs repeatedly, most hits never touch the rate limiter at all — cache-friendly clients effectively get more throughput for free.

Getting started

Concepts

Tools

Authentication & rate limits

Tiers

Using a key

Reading your limits

​Tiers

​Using a key

​Reading your limits

Tiers

Using a key

Reading your limits