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docs/minetest_client.md

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+# Minetest's use of the API
+
+This document explains how Minetest's ContentDB client interacts with ContentDB.
+This is useful both for implementing your own client for ContentDB to install mods, 
+or for implementing ContentDB compatible servers.
+
+## Package List API call
+
+The first request the client makes is to `/api/packages/`.
+The client will provide a list of supported types, the current engine version information,
+and any hidden [Content Flags](https://content.minetest.net/help/content_flags/).
+
+Because the client specifies the engine version information, the response must contain a release
+number and the package must be downloadable.
+
+Example URL:
+<https://content.minetest.net/api/packages/?type=mod&type=game&type=txp&protocol_version=39&engine_version=5.3.0&hide=nonfree&hide=desktop_default>
+
+Example response:
+
+```json
+[
+    {
+        "author": "Wuzzy",
+        "name": "mineclone2",
+        "release": 4209,
+        "short_description": "A short description",
+        "thumbnail": "https://content.minetest.net/thumbnails/1/tgbH5CwlAZ.jpg",
+        "title": "MineClone 2",
+        "type": "game"
+    }
+]
+```
+
+## Screenshots
+
+The client can simply download the URL mentioned in `thumbnail`.
+
+## Downloading and installing
+
+The client downloads packages by constructing a URL for the release and downloading it:
+
+```
+https://content.minetest.net/packages/<author>/<name>/releases/<release>/download/
+```
+
+This supports redirects.
+
+The client will edit the .conf of the installed content to add `author`, `name`, and `release` to
+track the installed release to detect updates in the future.
+
+## View in browser
+
+The client will open the package in a browser by constructing the following URL
+
+```
+https://content.minetest.net/packages/<author>/<name>/
+```