Issue with HDRI and Baked Lighting on Custom Shaders in Shader Graph

Hello,

I’m encountering an issue with custom shaders I create in Shader Graph. The baked lights affect the materials from Shader Graph minimally—it’s almost invisible most of the time. While it’s not ideal, I can somewhat work around this by placing objects with the custom material on a separate layer and adjusting the light render layers to match. However, I’m struggling with HDRI lighting.

When using HDRI, the custom shaders barely respond to the lighting. In the attached image, you can see my shader graph, material setup, and scene views under different lighting setups. The red material uses Unity’s URP Lit shader, which lights the strap perfectly with HDRI. But the material on the right is a custom shader, and HDRI barely affects it. I’ve tried tweaking the smoothness, ambient, and specular settings, but I can’t seem to get a properly lit material.

_What could be causing HDRI to have such a minimal effect on the custom shader?
_Why might baked lights, in general, have such a minimal effect in my shaders? Could it be that I haven’t set emission and ambient correctly?
_Should I be adding light probe and cubemap nodes to the shader? If so, where would be the best place to add them, and which output nodes should they connect to?

Thanks in advance!