OpenRouter, one endpoint in front of hundreds of models

One endpoint reaches hundreds of models, which turns the question every engagement opens with, which model should this use, from a week of separate integrations into an afternoon of changing a string. Automatic fallbacks mean a provider outage degrades rather than stops you. Version aliases resolve to the latest release, which is convenient during evaluation and a decision you should make deliberately later. The part that earns the most credit is the data policy surface, and it is better designed than most of the industry's. You can set at account level whether requests may route to providers that might train on your data, with separate controls for paid and free models, and you can constrain an individual request the same way. Rather than asserting one uniform standard, they publish each provider's retention policy so you can exclude the ones that fail your client's bar. That is a genuinely useful control, and building it required admitting the problem exists.

You are adding a third party to the data path, and that is frequently the sentence that ends a client's security review regardless of how good the controls are. Their own documentation is straight about it: opting out of provider training has no bearing on what OpenRouter itself does with your prompts. Reading that plainly stated is reassuring about their honesty and clarifying about the risk. Then there is provider variability. The same model name can be served by different backends with different latency, different quantisation and different throughput, so a benchmark you ran last week may not describe what your users get today, and diagnosing that from your side is difficult. The commercial terms also take work to pin down: neither the quickstart nor the privacy documentation states the fee model, so what this costs relative to going direct is not answerable from the pages a new user reads.

Spend an hour on it while you are still choosing, because comparing eight models across three vendors through one interface is worth several days. Skip it for production traffic in any engagement where a third party in the data path is not acceptable, which is most regulated clients. If you do keep it, set the account-level data policy before the first real prompt rather than after.

LiteLLM's proxy when you need the same abstraction but hosted inside the client's own network.