diff --git a/doc/specs/schemas/ArenaPosition.yaml b/doc/specs/schemas/ArenaPosition.yaml
index 1a98f15..d3dc16a 100644
--- a/doc/specs/schemas/ArenaPosition.yaml
+++ b/doc/specs/schemas/ArenaPosition.yaml
@@ -13,6 +13,7 @@ oneOf:
         example: 'rnbqkbnr/ppp2ppp/3p4/4p3/4P3/5N2/PPPP1PPP/RNBQKB1R w KQkq -'
       url:
         type: string
+        format: uri
         example: 'https://lichess.org/opening/Philidor_Defense'
   - type: object
     title: Custom position
diff --git a/doc/specs/schemas/BroadcastRoundForm.yaml b/doc/specs/schemas/BroadcastRoundForm.yaml
index 9cc8a8a..0f5d620 100644
--- a/doc/specs/schemas/BroadcastRoundForm.yaml
+++ b/doc/specs/schemas/BroadcastRoundForm.yaml
@@ -9,10 +9,11 @@ properties:
       Example: `Round 1`
   syncUrl:
     type: string
+    format: uri
     description: |
       URL that Lichess will poll to get updates about the games. It must be publicly accessible from the Internet.
       
-      Example: 
+      Example:
       ```txt
       https://myserver.org/myevent/round-10/games.pgn
       ```
@@ -21,9 +22,9 @@ properties:
   syncUrls:
     type: string
     description: |
-      URLs that Lichess will poll to get updates about the games. It must be publicly accessible from the Internet.
+      URLs that Lichess will poll to get updates about the games, separated by newlines. They must be publicly accessible from the Internet.
       
-      Example: 
+      Example:
       ```txt
       https://myserver.org/myevent/round-10/game-1.pgn
       https://myserver.org/myevent/round-10/game-2.pgn
@@ -34,7 +35,7 @@ properties:
     type: string
     description: |
       Lichess game IDs - Up to 64 Lichess game IDs, separated by spaces.
-      
+      on
       Choose one between `syncUrl`, `syncUrls` and `syncIds`, if it is missing, the broadcast needs to be fed by [pushing PGN to it](#operation/broadcastPush)
   onlyRound:
     type: integer
@@ -97,6 +98,6 @@ properties:
       (Only for Admins) Waiting time for each poll.
     minimum: 2
     maximum: 60
-          
+
 required:
-  - name
\ No newline at end of file
+  - name
diff --git a/doc/specs/schemas/BroadcastRoundInfo.yaml b/doc/specs/schemas/BroadcastRoundInfo.yaml
index ce4fddd..f4ea070 100644
--- a/doc/specs/schemas/BroadcastRoundInfo.yaml
+++ b/doc/specs/schemas/BroadcastRoundInfo.yaml
@@ -22,6 +22,7 @@ properties:
     type: boolean
   url:
     type: string
+    format: uri
   delay:
     type: integer
     format: int64
diff --git a/doc/specs/schemas/BroadcastTour.yaml b/doc/specs/schemas/BroadcastTour.yaml
index c9ac9f0..66784f2 100644
--- a/doc/specs/schemas/BroadcastTour.yaml
+++ b/doc/specs/schemas/BroadcastTour.yaml
@@ -55,6 +55,7 @@ properties:
     description: "Used to designate featured tournaments on Lichess"
   image:
     type: string
+    format: uri
   description:
     type: string
     description: "Full tournament description in markdown format, or in HTML if the html=1 query parameter is set."
@@ -64,6 +65,7 @@ properties:
     type: boolean
   url:
     type: string
+    format: uri
 
 required:
   - id
diff --git a/doc/specs/schemas/ChallengeJson.yaml b/doc/specs/schemas/ChallengeJson.yaml
index 18b4b2d..6cbc1eb 100644
--- a/doc/specs/schemas/ChallengeJson.yaml
+++ b/doc/specs/schemas/ChallengeJson.yaml
@@ -4,6 +4,7 @@ properties:
     type: string
   url:
     type: string
+    format: uri
   status:
     type: string
     enum:
diff --git a/doc/specs/schemas/ChallengeOpenJson.yaml b/doc/specs/schemas/ChallengeOpenJson.yaml
index cb61af1..2c46e5d 100644
--- a/doc/specs/schemas/ChallengeOpenJson.yaml
+++ b/doc/specs/schemas/ChallengeOpenJson.yaml
@@ -4,6 +4,7 @@ properties:
     type: string
   url:
     type: string
+    format: uri
   status:
     type: string
     enum: