Concept
One TXT record points, the document describes
A single DNS TXT record at _agent.<domain> carries v=agent1 and the https URL of the domain’s agent/1 document — DNS does the pointing, the well-known document does the describing.
Pinned to
agent-dns/1 — the discovery naming layerThe canonical source this concept is taught from. If it moves, the lesson is regenerated — teaching is pinned to code, not retyped.
On the frontier
No course teaches this concept yet — it is a named gap on the content graph, not a hole nobody sees. A gap is the roadmap, not an embarrassment: the count only falls by teaching.