moving input item from MCP Protocol back to core Protocol (#1740)

- Currently we have duplicate input item. Let's have one source of truth
in the core.
- Used Requestid type

codex-rs/mcp-server/src/mcp_protocol.rs

@@ -1,6 +1,7 @@
 use codex_core::config_types::SandboxMode;
 use codex_core::protocol::AskForApproval;
 use codex_core::protocol::EventMsg;
+use codex_core::protocol::InputItem;
 use serde::Deserialize;
 use serde::Serialize;
 use strum_macros::Display;
@@ -21,7 +22,7 @@ pub struct MessageId(pub Uuid);
 pub struct ToolCallRequest {
     #[serde(rename = "jsonrpc")]
     pub jsonrpc: &'static str,
-    pub id: u64,
+    pub id: RequestId,
     pub method: &'static str,
     pub params: ToolCallRequestParams,
 }
@@ -38,7 +39,7 @@ pub enum ToolCallRequestParams {
 impl ToolCallRequestParams {
     /// Wrap this request in a JSON-RPC request.
     #[allow(dead_code)]
-    pub fn into_request(self, id: u64) -> ToolCallRequest {
+    pub fn into_request(self, id: RequestId) -> ToolCallRequest {
         ToolCallRequest {
             jsonrpc: "2.0",
             id,
@@ -95,70 +96,13 @@ pub struct ConversationStreamArgs {
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
 pub struct ConversationSendMessageArgs {
     pub conversation_id: ConversationId,
-    pub content: Vec<MessageInputItem>,
+    pub content: Vec<InputItem>,
     #[serde(default, skip_serializing_if = "Option::is_none")]
     pub parent_message_id: Option<MessageId>,
     #[serde(default, skip_serializing_if = "Option::is_none")]
     #[serde(flatten)]
     pub conversation_overrides: Option<ConversationOverrides>,
 }
-
-/// Input items for a message.
-/// Following OpenAI's Responses API: https://platform.openai.com/docs/api-reference/responses
-#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
-#[serde(tag = "type", rename_all = "camelCase")]
-pub enum MessageInputItem {
-    Text {
-        text: String,
-    },
-    Image {
-        #[serde(flatten)]
-        source: ImageSource,
-        #[serde(default, skip_serializing_if = "Option::is_none")]
-        detail: Option<ImageDetail>,
-    },
-    File {
-        #[serde(flatten)]
-        source: FileSource,
-    },
-}
-
-/// Source of an image.
-/// Following OpenAI's API: https://platform.openai.com/docs/guides/images-vision#giving-a-model-images-as-input
-#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
-#[serde(untagged)]
-pub enum ImageSource {
-    ImageUrl { image_url: String },
-    FileId { file_id: String },
-}
-
-/// Source of a file.
-/// Following OpenAI's Responses API: https://platform.openai.com/docs/guides/pdf-files?api-mode=responses#uploading-files
-#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
-#[serde(untagged)]
-pub enum FileSource {
-    Url {
-        file_url: String,
-    },
-    Id {
-        file_id: String,
-    },
-    Base64 {
-        #[serde(default, skip_serializing_if = "Option::is_none")]
-        filename: Option<String>,
-        // Base64-encoded file contents.
-        file_data: String,
-    },
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, Serialize, Deserialize)]
-#[serde(rename_all = "camelCase")]
-pub enum ImageDetail {
-    Low,
-    High,
-    Auto,
-}
-
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
 pub struct ConversationsListArgs {
     #[serde(default, skip_serializing_if = "Option::is_none")]
@@ -303,6 +247,8 @@ pub enum ClientNotification {
 #[allow(clippy::expect_used)]
 #[allow(clippy::unwrap_used)]
 mod tests {
+    use std::path::PathBuf;
+
     use super::*;
     use codex_core::protocol::McpInvocation;
     use codex_core::protocol::McpToolCallBeginEvent;
@@ -331,7 +277,7 @@ mod tests {
             base_instructions: None,
         });
 
-        let observed = to_val(&req.into_request(2));
+        let observed = to_val(&req.into_request(mcp_types::RequestId::Integer(2)));
         let expected = json!({
             "jsonrpc": "2.0",
             "id": 2,
@@ -354,18 +300,12 @@ mod tests {
         let req = ToolCallRequestParams::ConversationSendMessage(ConversationSendMessageArgs {
             conversation_id: ConversationId(uuid!("d0f6ecbe-84a2-41c1-b23d-b20473b25eab")),
             content: vec![
-                MessageInputItem::Text { text: "Hi".into() },
+                InputItem::Text { text: "Hi".into() },
-                MessageInputItem::Image {
+                InputItem::Image {
-                    source: ImageSource::ImageUrl {
+                    image_url: "https://example.com/cat.jpg".into(),
-                        image_url: "https://example.com/cat.jpg".into(),
-                    },
-                    detail: Some(ImageDetail::High),
                 },
-                MessageInputItem::File {
+                InputItem::LocalImage {
-                    source: FileSource::Base64 {
+                    path: "notes.txt".into(),
-                        filename: Some("notes.txt".into()),
-                        file_data: "Zm9vYmFy".into(),
-                    },
                 },
             ],
             parent_message_id: Some(MessageId(uuid!("67e55044-10b1-426f-9247-bb680e5fe0c8"))),
@@ -380,7 +320,7 @@ mod tests {
             }),
         });
 
-        let observed = to_val(&req.into_request(2));
+        let observed = to_val(&req.into_request(mcp_types::RequestId::Integer(2)));
         let expected = json!({
             "jsonrpc": "2.0",
             "id": 2,
@@ -391,8 +331,8 @@ mod tests {
                     "conversation_id": "d0f6ecbe-84a2-41c1-b23d-b20473b25eab",
                     "content": [
                         { "type": "text", "text": "Hi" },
-                        { "type": "image", "image_url": "https://example.com/cat.jpg", "detail": "high" },
+                        { "type": "image", "image_url": "https://example.com/cat.jpg" },
-                        { "type": "file", "filename": "notes.txt", "file_data": "Zm9vYmFy" }
+                        { "type": "local_image", "path": "notes.txt" }
                     ],
                     "parent_message_id": "67e55044-10b1-426f-9247-bb680e5fe0c8",
                     "model": "o4-mini",
@@ -414,7 +354,7 @@ mod tests {
             cursor: Some("abc".into()),
         });
 
-        let observed = to_val(&req.into_request(2));
+        let observed = to_val(&req.into_request(RequestId::Integer(2)));
         let expected = json!({
             "jsonrpc": "2.0",
             "id": 2,
@@ -436,7 +376,7 @@ mod tests {
             conversation_id: ConversationId(uuid!("67e55044-10b1-426f-9247-bb680e5fe0c8")),
         });
 
-        let observed = to_val(&req.into_request(2));
+        let observed = to_val(&req.into_request(mcp_types::RequestId::Integer(2)));
         let expected = json!({
             "jsonrpc": "2.0",
             "id": 2,
@@ -454,48 +394,44 @@ mod tests {
     // ----- Message inputs / sources -----
 
     #[test]
-    fn serialize_message_input_image_file_id_auto_detail() {
+    fn serialize_message_input_image_url() {
-        let item = MessageInputItem::Image {
+        let item = InputItem::Image {
-            source: ImageSource::FileId {
+            image_url: "https://example.com/x.png".into(),
-                file_id: "file_123".into(),
-            },
-            detail: Some(ImageDetail::Auto),
         };
         let observed = to_val(&item);
         let expected = json!({
             "type": "image",
-            "file_id": "file_123",
+            "image_url": "https://example.com/x.png"
-            "detail": "auto"
         });
         assert_eq!(observed, expected);
     }
 
     #[test]
-    fn serialize_message_input_file_url_and_id_variants() {
+    fn serialize_message_input_local_image_path() {
-        let url = MessageInputItem::File {
+        let url = InputItem::LocalImage {
-            source: FileSource::Url {
+            path: PathBuf::from("https://example.com/a.pdf"),
-                file_url: "https://example.com/a.pdf".into(),
-            },
         };
-        let id = MessageInputItem::File {
+        let id = InputItem::LocalImage {
-            source: FileSource::Id {
+            path: PathBuf::from("file_456"),
-                file_id: "file_456".into(),
-            },
         };
+        let observed_url = to_val(&url);
+        let expected_url = json!({"type":"local_image","path":"https://example.com/a.pdf"});
         assert_eq!(
-            to_val(&url),
+            observed_url, expected_url,
-            json!({"type":"file","file_url":"https://example.com/a.pdf"})
+            "LocalImage with URL path should serialize as image_url"
+        );
+        let observed_id = to_val(&id);
+        let expected_id = json!({"type":"local_image","path":"file_456"});
+        assert_eq!(
+            observed_id, expected_id,
+            "LocalImage with file id should serialize as image_url"
         );
-        assert_eq!(to_val(&id), json!({"type":"file","file_id":"file_456"}));
     }
 
     #[test]
     fn serialize_message_input_image_url_without_detail() {
-        let item = MessageInputItem::Image {
+        let item = InputItem::Image {
-            source: ImageSource::ImageUrl {
+            image_url: "https://example.com/x.png".into(),
-                image_url: "https://example.com/x.png".into(),
-            },
-            detail: None,
         };
         let observed = to_val(&item);
         let expected = json!({