Would you lead with the AI gateway or the free stock researcher?

I'd lead with the gateway and use the stock researcher as the concrete demo. If the first thing people see is stock researcher, you pull in curiosity from the wrong audience and spend the rest of the page re-explaining yourself. We ran into the same thing with DictaFlow. When we lead with AI cleanup, people assume AI writer, but when we lead with hold-to-talk dictation that types into the current app, the product clicks faster. The example should make the core product obvious, not compete with it.

Leading with the free stock researcher gets you users faster but you risk becoming known as a stock tool that happens to also have a gateway, which is a hard story to walk back later. Leading with the gateway is slower but the identity is correct from day one.
The commit to one angle advice is right, but I'd pick based on which one your actual early users keep talking about unprompted. If people who try the stock researcher start asking about the gateway on their own, that tells you the order that's working in practice, not just in theory.

I’d keep it simple — lead with the API gateway, but show the researcher right away.

If you lead with the stock researcher, people might think it’s a finance product and miss the actual value. But if you only talk about the gateway, it can feel abstract.

The researcher makes it click fast. It’s like: “oh, this is what I can actually do with it.”

So yeah, I’d position it more like:
core product = gateway
research tool = real example of what it enables

That way it adds clarity instead of distracting.

I'd lead with the API gateway. That's the product people pay for. The stock researcher works well as proof of what's possible with the gateway, but if it's the first thing people see, they may assume you're building an investing tool instead of AI infrastructure.