Developers know that it's a good idea to carefully read the terms of service (ToS) for APIs you use. However, it's all too easy to ignore a ToS as nothing more than legal boilerplate.
Occasionally, you find some pretty unusual terms. Consider the ESV Bible Lookup API, mentioned in a previous story on New APIs: Games, Shopping and the Bible. Among the conditions of use for the API are the following statements:
This service is available for use only by individuals and non-commercial organizations that use the service in ways consistent with the historic Christian understanding of doctrine and the Bible, as summarized in the following foundational doctrines....You agree to maintain the moral integrity, spirit, fervor, and consistency in message that is inherent in the nature of the ESV Bible. This means that your use is consistent with the above statement of faith and that you give proper attribution.
It's probably safe to say that few APIs require this level of moral introspection to use. How can one even tell that you are complying with these conditions? Ultimately, there may be no need to answer this question since there is a condition of use that trumps all others:
We reserve the right to cancel your access to the service at any time for any reason.