diff --git a/README.md b/README.md
index ed1700a29..d1333d720 100644
--- a/README.md
+++ b/README.md
@@ -10,6 +10,19 @@ Made by Vibe Coders for Vibe Coders to prepare the way of the Lord and make His
 iframe, script embed, mobile app — or open every map at once as one app. Five plugin
 capabilities, three outputs, one shared library, one build.
 
+### What the library gives every map
+
+| | |
+|---|---|
+| 🗺️ **Two map engines** | Every map draws with **Mapbox** or **MapLibre** (free, no key) — switch with `"provider"` in its settings or `?provider=maplibre` in the address. Mapbox is the default. |
+| 🔑 **A key or a key service** | Give Mapbox a public token, or the address of a token service that hands one out — set once in the Plugin Studio header. |
+| 🌍 **11 languages** | `?lang=` or `"locale"`, with Arabic right to left — [Languages](#languages). |
+| 🧩 **Web components** | Each map is its own HTML tag, like `<all-people-groups>`, that works on any page — no framework needed. |
+| 🔗 **Maps that talk to each other** | Maps share props and events, so one app can nest them and a click in one can move another. |
+| 🪶 **Small bundles** | Each map's file carries only the parts of the shared library it uses (tree-shaken). |
+| ⚙️ **One build step** | `bun run build` makes every map at once. |
+| 📦 **Three outputs** | A web folder (iframe, script embed), a mobile app, a desktop app — [the 3 outputs](#what-the-build-makes--3-outputs). |
+
 | What dx-maps set out to do | Proof |
 |---|---|
 | **One build → one folder** you can drop on any host | `bun run check:drop` |