Evaluation happens before contact
A buyer working out whether your product does what they need asks an assistant, which answers from whatever it can read. If your documentation sits behind a login, it answers from your competitor’s instead.
Docs are structurally ideal source material
Task-shaped headings, direct answers, specific facts, and self-contained sections. Documentation already has the properties that get content quoted, usually more than the marketing pages next to it.
Your best-structured content is probably your documentation, and it’s probably behind a login.
Gating it costs more than it protects
Hiding docs rarely prevents anything a competitor couldn’t learn from a trial. It reliably removes you from pre-purchase answers, which is the same trade-off as blocking AI crawlers when your content is marketing.
Publish the limits too
What the product doesn’t do, what it needs, and where it isn’t suitable. Those are the questions buyers actually ask, and being the source of an honest answer is worth more than an unqualified enquiry.
Stale docs damage more than they help
Documentation describing behaviour that changed is a page confidently telling buyers something false about you — the exact material that later requires correcting how you are described.
Link docs and marketing to each other
Service pages should link to the relevant documentation and back. That connection is how the depth in your docs lends authority to the pages that sell — internal linking doing commercial work.