diff --git a/doc/RFC.md b/doc/RFC.md
index 3753c33..28d21c0 100644
--- a/doc/RFC.md
+++ b/doc/RFC.md
@@ -4,10 +4,26 @@
 
 > version 1.0.0
 
-date: 2023-04-02T21:37:32+0200<br>
+date: 2023-04-06T18:27:40+0200<br>
 [![Actions Status](https://github.com/coderofsalvation/xrfragment/workflows/test/badge.svg)](https://github.com/coderofsalvation/xrfragment/actions)
 
-# `://foo.com/my3d.asset#pos=1,0,0&prio=-5`
+# XRFragment Grammar 
+
+```
+    reserved    = gen-delims / sub-delims
+    gen-delims  = "#" / "&"                      
+    sub-delims  = "," / "|" / "="
+```
+
+> Example: `://foo.com/my3d.asset#pos=1,0,0&prio=-5&t=0,100|100,200`
+
+| Delimiter example | info |
+|-|-|
+| x=1,2,3 | vector/coordinate argument e.g. |
+| x=foo\|bar\|1\,2,3\|1.0 | the `\|` character is used for:<br>1.specifying `n` arguments for xrfragment `x`<br>2. fallback urls (`src=https://x.co/f.gltf\|xyz://f.gltf`)<br>3. roundrobin of values (in case provided arguments exceeds `n` of `x` for #1) when triggered by browser URI (clicking `href` e.g.)|
+| .mygroup | query-alias for `class:mygroup` |
+
+> This allows hasslefree 3D vector-data (`,`), multi-protocol/fallback-linking & dynamic values (`|`), and CSS-piggybacking (`.mygroup`) 
 
 # URI parser
 > icanhazcode? yes, see [URI.hx](https://github.com/coderofsalvation/xrfragment/blob/main/src/xrfragment/URI.hx)
diff --git a/src/xrfragment/URI.hx b/src/xrfragment/URI.hx
index ed043aa..dbb444f 100644
--- a/src/xrfragment/URI.hx
+++ b/src/xrfragment/URI.hx
@@ -11,7 +11,23 @@ import xrfragment.Parser;
  * date: $(date +"%Y-%m-%dT%H:%M:%S%z") (generated by \`./make doc\`)<br>
  * [![Actions Status](https://github.com/coderofsalvation/xrfragment/workflows/test/badge.svg)](https://github.com/coderofsalvation/xrfragment/actions)
  *
- * # `://foo.com/my3d.asset#pos=1,0,0&prio=-5`
+ * # XRFragment Grammar 
+ *
+ * ```
+ *     reserved    = gen-delims / sub-delims
+ *     gen-delims  = "#" / "&"                      
+ *     sub-delims  = "," / "|" / "="
+ * ```
+ *
+ * > Example: `://foo.com/my3d.asset#pos=1,0,0&prio=-5&t=0,100|100,200`
+ *
+ * | Delimiter example | info |
+ * |-|-|
+ * | x=1,2,3 | vector/coordinate argument e.g. |
+ * | x=foo\|bar\|1\,2,3\|1.0 | the `\|` character is used for:<br>1.specifying `n` arguments for xrfragment `x`<br>2. fallback urls (`src=https://x.co/f.gltf\|xyz://f.gltf`)<br>3. roundrobin of values (in case provided arguments exceeds `n` of `x` for #1) when triggered by browser URI (clicking `href` e.g.)|
+ * | .mygroup | query-alias for `class:mygroup` |
+ *
+ * > This allows hasslefree 3D vector-data (`,`), multi-protocol/fallback-linking & dynamic values (`|`), and CSS-piggybacking (`.mygroup`) 
  *
  * # URI parser
  * > icanhazcode? yes, see [URI.hx](https://github.com/coderofsalvation/xrfragment/blob/main/src/xrfragment/URI.hx)