Added API.md

server/api/API.md

@@ -0,0 +1,45 @@
+# API
+
+All responses are returned as JSON over HTTP.
+
+## Root Endpoint
+
+The root endpoint for the API is http://favicongrabber.com/api/
+
+## Grab
+
+```
+GET /api/grab/:domain
+```
+
+For instance, to grab favicons of GitHub's index page:
+
+http://favicongrabber.com/api/grab/github.com
+
+```json
+{
+  "domain": "github.com",
+  "icons": [
+    {
+      "src": "https://assets-cdn.github.com/favicon.ico",
+      "type": "image/x-icon"
+    },
+    {
+      "src": "https://assets-cdn.github.com/pinned-octocat.svg"
+    },
+    {
+      "src": "https://github.com/fluidicon.png"
+    }
+  ]
+}
+```
+
+## Errors
+
+Error messages have the following format:
+
+```json
+{
+  "error": "Unresolved domain \"example.test\""
+}
+```