diff --git a/crates/rmcp/src/model/content.rs b/crates/rmcp/src/model/content.rs
index 7c75381..964f604 100644
--- a/crates/rmcp/src/model/content.rs
+++ b/crates/rmcp/src/model/content.rs
@@ -171,3 +171,40 @@ impl IntoContents for () {
         vec![]
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use serde_json;
+
+    use super::*;
+
+    #[test]
+    fn test_image_content_serialization() {
+        let image_content = RawImageContent {
+            data: "base64data".to_string(),
+            mime_type: "image/png".to_string(),
+        };
+
+        let json = serde_json::to_string(&image_content).unwrap();
+        println!("ImageContent JSON: {}", json);
+
+        // Verify it contains mimeType (camelCase) not mime_type (snake_case)
+        assert!(json.contains("mimeType"));
+        assert!(!json.contains("mime_type"));
+    }
+
+    #[test]
+    fn test_audio_content_serialization() {
+        let audio_content = RawAudioContent {
+            data: "base64audiodata".to_string(),
+            mime_type: "audio/wav".to_string(),
+        };
+
+        let json = serde_json::to_string(&audio_content).unwrap();
+        println!("AudioContent JSON: {}", json);
+
+        // Verify it contains mimeType (camelCase) not mime_type (snake_case)
+        assert!(json.contains("mimeType"));
+        assert!(!json.contains("mime_type"));
+    }
+}
diff --git a/crates/rmcp/src/model/prompt.rs b/crates/rmcp/src/model/prompt.rs
index adba236..9c6d3bb 100644
--- a/crates/rmcp/src/model/prompt.rs
+++ b/crates/rmcp/src/model/prompt.rs
@@ -168,3 +168,25 @@ pub struct PromptArgumentTemplate {
     pub description: Option<String>,
     pub required: Option<bool>,
 }
+
+#[cfg(test)]
+mod tests {
+    use serde_json;
+
+    use super::*;
+
+    #[test]
+    fn test_prompt_message_image_serialization() {
+        let image_content = RawImageContent {
+            data: "base64data".to_string(),
+            mime_type: "image/png".to_string(),
+        };
+
+        let json = serde_json::to_string(&image_content).unwrap();
+        println!("PromptMessage ImageContent JSON: {}", json);
+
+        // Verify it contains mimeType (camelCase) not mime_type (snake_case)
+        assert!(json.contains("mimeType"));
+        assert!(!json.contains("mime_type"));
+    }
+}
diff --git a/crates/rmcp/src/model/resource.rs b/crates/rmcp/src/model/resource.rs
index fe7d26c..cc8cb0b 100644
--- a/crates/rmcp/src/model/resource.rs
+++ b/crates/rmcp/src/model/resource.rs
@@ -42,15 +42,17 @@ pub struct RawResourceTemplate {
 pub type ResourceTemplate = Annotated<RawResourceTemplate>;
 
 #[derive(Debug, Serialize, Deserialize, Clone, PartialEq)]
-#[serde(rename_all = "camelCase", untagged)]
+#[serde(untagged)]
 #[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
 pub enum ResourceContents {
+    #[serde(rename_all = "camelCase")]
     TextResourceContents {
         uri: String,
         #[serde(skip_serializing_if = "Option::is_none")]
         mime_type: Option<String>,
         text: String,
     },
+    #[serde(rename_all = "camelCase")]
     BlobResourceContents {
         uri: String,
         #[serde(skip_serializing_if = "Option::is_none")]
@@ -81,3 +83,44 @@ impl RawResource {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use serde_json;
+
+    use super::*;
+
+    #[test]
+    fn test_resource_serialization() {
+        let resource = RawResource {
+            uri: "file:///test.txt".to_string(),
+            name: "test".to_string(),
+            description: Some("Test resource".to_string()),
+            mime_type: Some("text/plain".to_string()),
+            size: Some(100),
+        };
+
+        let json = serde_json::to_string(&resource).unwrap();
+        println!("Serialized JSON: {}", json);
+
+        // Verify it contains mimeType (camelCase) not mime_type (snake_case)
+        assert!(json.contains("mimeType"));
+        assert!(!json.contains("mime_type"));
+    }
+
+    #[test]
+    fn test_resource_contents_serialization() {
+        let text_contents = ResourceContents::TextResourceContents {
+            uri: "file:///test.txt".to_string(),
+            mime_type: Some("text/plain".to_string()),
+            text: "Hello world".to_string(),
+        };
+
+        let json = serde_json::to_string(&text_contents).unwrap();
+        println!("ResourceContents JSON: {}", json);
+
+        // Verify it contains mimeType (camelCase) not mime_type (snake_case)
+        assert!(json.contains("mimeType"));
+        assert!(!json.contains("mime_type"));
+    }
+}
diff --git a/crates/rmcp/tests/test_message_schema/client_json_rpc_message_schema.json b/crates/rmcp/tests/test_message_schema/client_json_rpc_message_schema.json
index 2ddebc7..5dbc97f 100644
--- a/crates/rmcp/tests/test_message_schema/client_json_rpc_message_schema.json
+++ b/crates/rmcp/tests/test_message_schema/client_json_rpc_message_schema.json
@@ -1129,7 +1129,7 @@
         {
           "type": "object",
           "properties": {
-            "mime_type": {
+            "mimeType": {
               "type": [
                 "string",
                 "null"
@@ -1153,7 +1153,7 @@
             "blob": {
               "type": "string"
             },
-            "mime_type": {
+            "mimeType": {
               "type": [
                 "string",
                 "null"
diff --git a/crates/rmcp/tests/test_message_schema/server_json_rpc_message_schema.json b/crates/rmcp/tests/test_message_schema/server_json_rpc_message_schema.json
index 5cac39c..2d63467 100644
--- a/crates/rmcp/tests/test_message_schema/server_json_rpc_message_schema.json
+++ b/crates/rmcp/tests/test_message_schema/server_json_rpc_message_schema.json
@@ -1333,7 +1333,7 @@
         {
           "type": "object",
           "properties": {
-            "mime_type": {
+            "mimeType": {
               "type": [
                 "string",
                 "null"
@@ -1357,7 +1357,7 @@
             "blob": {
               "type": "string"
             },
-            "mime_type": {
+            "mimeType": {
               "type": [
                 "string",
                 "null"