feat: ToolError migration to ErrorData (#4051)

crates/goose/src/conversation/message.rs

@@ -603,12 +603,12 @@ impl Message {
 mod tests {
     use crate::conversation::message::{Message, MessageContent};
     use crate::conversation::*;
-    use mcp_core::handler::ToolError;
     use mcp_core::ToolCall;
     use rmcp::model::{
         AnnotateAble, PromptMessage, PromptMessageContent, PromptMessageRole, RawEmbeddedResource,
         RawImageContent, ResourceContents,
     };
+    use rmcp::model::{ErrorCode, ErrorData};
     use serde_json::{json, Value};
 
     #[test]
@@ -683,9 +683,11 @@ mod tests {
     fn test_error_serialization() {
         let message = Message::assistant().with_tool_request(
             "tool123",
-            Err(ToolError::ExecutionError(
-                "Something went wrong".to_string(),
-            )),
+            Err(ErrorData {
+                code: ErrorCode::INTERNAL_ERROR,
+                message: std::borrow::Cow::from("Something went wrong".to_string()),
+                data: None,
+            }),
         );
 
         let json_str = serde_json::to_string_pretty(&message).unwrap();
@@ -697,7 +699,7 @@ mod tests {
         // Check tool_call serialization with error
         let tool_call = &value["content"][0]["toolCall"];
         assert_eq!(tool_call["status"], "error");
-        assert_eq!(tool_call["error"], "Execution failed: Something went wrong");
+        assert_eq!(tool_call["error"], "-32603: Something went wrong");
     }
 
     #[test]

crates/goose/src/conversation/tool_result_serde.rs

@@ -1,6 +1,8 @@
-use mcp_core::handler::{ToolError, ToolResult};
+use mcp_core::ToolResult;
+use rmcp::model::{ErrorCode, ErrorData};
 use serde::ser::SerializeStruct;
 use serde::{Deserialize, Deserializer, Serialize, Serializer};
+use std::borrow::Cow;
 
 pub fn serialize<T, S>(value: &ToolResult<T>, serializer: S) -> Result<S::Ok, S::Error>
 where
@@ -52,7 +54,11 @@ where
         }
         ResultFormat::Error { status, error } => {
             if status == "error" {
-                Ok(Err(ToolError::ExecutionError(error)))
+                Ok(Err(ErrorData {
+                    code: ErrorCode::INTERNAL_ERROR,
+                    message: Cow::from(error),
+                    data: None,
+                }))
             } else {
                 Err(serde::de::Error::custom(format!(
                     "Expected status 'error', got '{}'",