FEP-0151: Capability detection (#604)

- Updated "Capability detection" section.
- Improved `metadata` example.

Reviewed-on: https://codeberg.org/fediverse/fep/pulls/604
Co-authored-by: silverpill <silverpill@firemail.cc>
Co-committed-by: silverpill <silverpill@firemail.cc>

fep/0151/fep-0151.md

@@ -27,7 +27,7 @@ Servers SHOULD implement [NodeInfo protocol version 2.1][NodeInfo].
 
 Some information contained in the NodeInfo document might be considered sensitive by server operators.
 
-The NodeInfo endpoint could be disabled to hide that information. Servers MUST NOT publish incorrect software metadata.
+The NodeInfo endpoint could be disabled to hide that information.
 
 ### Hiding usage statistics
 
@@ -43,11 +43,11 @@ All numeric properties in the `usage` object are optional and could be omitted t
 
 Servers MUST NOT publish incorrect usage statistics.
 
-### When to use NodeInfo
+### Capability detection
 
-Server operators might intentionally disable NodeInfo, therefore applications SHOULD NOT rely on NodeInfo data for protocol negotiation and capability detection.
+Servers SHOULD NOT rely on NodeInfo data for protocol negotiation and capability detection because server operators might intentionally disable NodeInfo. Servers MUST NOT infer capabilities from the `software` field and MUST treat `software.name` and `software.version` values as opaque strings.
 
-Protocol-specific mechanisms could be used instead.
+Protocol-specific capability discovery mechanisms could be used instead.
 
 ### `metadata`
 
@@ -62,13 +62,15 @@ Example:
 
 ```json
 {
-  "nodeName": "My server",
-  "nodeDescription": "My server",
-  "staffAccounts": [
-    "https://social.example/actors/1"
-  ],
-  "federation": {
-    "enabled": true
+  "metadata": {
+    "nodeName": "My server",
+    "nodeDescription": "My server",
+    "staffAccounts": [
+      "https://social.example/actors/1"
+    ],
+    "federation": {
+      "enabled": true
+    }
   }
 }
 ```