One thing I've seen more than once in integration work is this: the vendor API becomes the problem. At the start, it always looks straightforward. There's an API, the docs exist, and the plan seems clear enough. Then the real work starts. A field comes back in a different format than expected. An endpoint works in one environment and then acts differently in another. Something that looked fine in testing starts failing once real data or real usage hits it. We have also had cases where the docs looked fine, but the actual response shape coming back from the API was not something we could safely trust. Or the API works, but not well enough to build the rest of the project around it with any confidence. That is usually the point where you have to make a choice. You can wait for the vendor to sort it out, which usually means your timeline starts depending on theirs. Or you can accept that the API is not stable enough and design around that. Most of the time, I would rather do the second.…