API Terms of Service

Last updated: March 18, 2026

1. Acceptance

By using the SPINES API ("API"), you agree to these API Terms of Service in addition to the general Terms of Use. If you do not agree, do not use the API.

2. API Access

API access requires an API key obtained through your SPINES account settings. You are responsible for the security of your API keys and all activity performed with them.

  • Do not share API keys publicly or embed them in client-side code
  • Rotate keys immediately if you suspect they have been compromised
  • Each user may have up to 10 active API keys

3. Rate Limits

The free API tier includes:

  • 30 requests per minute (burst limit)
  • 1,000 read requests per day
  • 200 write requests per day
  • 10 recognition credits per day

Exceeding rate limits returns HTTP 429. The Retry-After header indicates when to retry.

4. Permitted Use

You may use the API to:

  • Build applications that integrate with SPINES data
  • Access and manage your own collections and reading lists
  • Search and display book information
  • Recognize books from bookshelf images (within credit limits)

5. Prohibited Use

You must not:

  • Scrape or bulk-download data beyond reasonable application use
  • Circumvent rate limits using multiple accounts or keys
  • Use the API for competing services that replicate SPINES core functionality
  • Redistribute raw API data as a dataset
  • Use recognition endpoints to process images unrelated to bookshelves
  • Attempt to reverse-engineer the recognition models

6. Data & Attribution

When displaying data from the SPINES API in your application, please include attribution such as "Powered by SPINES" or a link to getspines.com.

Book metadata may originate from third-party sources (Google Books, Open Library). You are responsible for complying with their respective terms of service.

7. Test Mode

Test-mode keys (prefix gtspn_test_) return synthetic data and do not affect production data. Use test keys for development and testing.

8. Termination

We may revoke API access at any time for violations of these terms or the general Terms of Use. You may revoke your own API keys at any time through your account settings.

9. Changes

We may update these API terms at any time. Continued use of the API after changes constitutes acceptance of the updated terms. Breaking API changes will be communicated with at least 30 days notice.

10. Contact

For API-related questions: support@getspines.com