diff --git a/lexicons/app/bsky/actor/defs.json b/lexicons/app/bsky/actor/defs.json
index 1ad8493002e..45f7386945f 100644
--- a/lexicons/app/bsky/actor/defs.json
+++ b/lexicons/app/bsky/actor/defs.json
@@ -13,7 +13,7 @@
           "maxGraphemes": 64,
           "maxLength": 640
         },
-        "avatar": { "type": "string" },
+        "avatar": { "type": "string", "format": "uri" },
         "associated": {
           "type": "ref",
           "ref": "#profileAssociated"
@@ -41,7 +41,7 @@
           "maxGraphemes": 256,
           "maxLength": 2560
         },
-        "avatar": { "type": "string" },
+        "avatar": { "type": "string", "format": "uri" },
         "associated": {
           "type": "ref",
           "ref": "#profileAssociated"
@@ -70,8 +70,8 @@
           "maxGraphemes": 256,
           "maxLength": 2560
         },
-        "avatar": { "type": "string" },
-        "banner": { "type": "string" },
+        "avatar": { "type": "string", "format": "uri" },
+        "banner": { "type": "string", "format": "uri" },
         "followersCount": { "type": "integer" },
         "followsCount": { "type": "integer" },
         "postsCount": { "type": "integer" },
diff --git a/lexicons/app/bsky/embed/external.json b/lexicons/app/bsky/embed/external.json
index b9c8c1596d5..b9930dff2b0 100644
--- a/lexicons/app/bsky/embed/external.json
+++ b/lexicons/app/bsky/embed/external.json
@@ -44,7 +44,7 @@
         "uri": { "type": "string", "format": "uri" },
         "title": { "type": "string" },
         "description": { "type": "string" },
-        "thumb": { "type": "string" }
+        "thumb": { "type": "string", "format": "uri" }
       }
     }
   }
diff --git a/lexicons/app/bsky/embed/images.json b/lexicons/app/bsky/embed/images.json
index 307607bb7c2..7de9d7a862d 100644
--- a/lexicons/app/bsky/embed/images.json
+++ b/lexicons/app/bsky/embed/images.json
@@ -56,10 +56,12 @@
       "properties": {
         "thumb": {
           "type": "string",
+          "format": "uri",
           "description": "Fully-qualified URL where a thumbnail of the image can be fetched. For example, CDN location provided by the App View."
         },
         "fullsize": {
           "type": "string",
+          "format": "uri",
           "description": "Fully-qualified URL where a large version of the image can be fetched. May or may not be the exact original blob. For example, CDN location provided by the App View."
         },
         "alt": {
diff --git a/lexicons/app/bsky/feed/defs.json b/lexicons/app/bsky/feed/defs.json
index 7c40ef3962f..0a83fa71a2a 100644
--- a/lexicons/app/bsky/feed/defs.json
+++ b/lexicons/app/bsky/feed/defs.json
@@ -135,7 +135,7 @@
           "type": "array",
           "items": { "type": "ref", "ref": "app.bsky.richtext.facet" }
         },
-        "avatar": { "type": "string" },
+        "avatar": { "type": "string", "format": "uri" },
         "likeCount": { "type": "integer", "minimum": 0 },
         "labels": {
           "type": "array",
diff --git a/lexicons/app/bsky/graph/defs.json b/lexicons/app/bsky/graph/defs.json
index be718f20a16..0b94a21ec87 100644
--- a/lexicons/app/bsky/graph/defs.json
+++ b/lexicons/app/bsky/graph/defs.json
@@ -10,7 +10,7 @@
         "cid": { "type": "string", "format": "cid" },
         "name": { "type": "string", "maxLength": 64, "minLength": 1 },
         "purpose": { "type": "ref", "ref": "#listPurpose" },
-        "avatar": { "type": "string" },
+        "avatar": { "type": "string", "format": "uri" },
         "labels": {
           "type": "array",
           "items": { "type": "ref", "ref": "com.atproto.label.defs#label" }
@@ -37,7 +37,7 @@
           "type": "array",
           "items": { "type": "ref", "ref": "app.bsky.richtext.facet" }
         },
-        "avatar": { "type": "string" },
+        "avatar": { "type": "string", "format": "uri" },
         "labels": {
           "type": "array",
           "items": { "type": "ref", "ref": "com.atproto.label.defs#label" }