How to Choose Free APIs and Relay Services? I Made a Directory That Only Lists Real Conditions

I often look for free APIs and relay services, and what annoys me most is directories that only say "free" without the conditions. A service can look free at first glance, but then turn out to require a daily action, work only in a particular setup, or behave differently from what the headline suggests. That is why I put together a directory that only lists real conditions: https://gsb.cc.cd/

The point is not to collect as many links as possible. Each entry lists its quota and limits, so you can judge whether it actually fits how you plan to use it before you sign up or spend time setting it up.

For example, the conditions I list include cases like these:

• Some entries give credit through daily check-in, so the free credit depends on whether you keep checking in.
• One entry's free credit only works in a self-built group, so it is not the same as credit you can use anywhere without that setup.
• Some low-rate groups are degraded while others are not, so a lower rate does not automatically mean the same experience.
• One entry's Claude availability is untested, and I say so instead of claiming it works.

There is also a different kind of entry worth checking carefully: one entry notes a promo code for first-year free .tech domain registration. If you use it, remember to turn off paid privacy protection and confirm the first-year total is $0 before checkout.

Policies change often, so the official site of each service always prevails. Treat the directory as a starting point for comparison, not as a promise that a condition will stay the same.

If you have tried any of these, I would like to hear which conditions you actually hit. Did a daily check-in, a group-only restriction, or a degraded low-rate group change how useful the service was for you?