diff --git a/libs/app-error/src/lib.rs b/libs/app-error/src/lib.rs
index 4df946f1d..0ba39eefc 100644
--- a/libs/app-error/src/lib.rs
+++ b/libs/app-error/src/lib.rs
@@ -3,6 +3,7 @@ pub mod gotrue;
 
 #[cfg(feature = "gotrue_error")]
 use crate::gotrue::GoTrueError;
+use std::error::Error;
 use std::string::FromUtf8Error;
 
 #[cfg(feature = "appflowy_ai_error")]
@@ -277,13 +278,32 @@ impl From<reqwest::Error> for AppError {
       return AppError::RequestTimeout(error.to_string());
     }
 
-    if error.is_request() {
-      return if error.status() == Some(StatusCode::PAYLOAD_TOO_LARGE) {
-        AppError::PayloadTooLarge(error.to_string())
-      } else {
-        AppError::InvalidRequest(error.to_string())
-      };
+    if let Some(cause) = error.source() {
+      if cause
+        .to_string()
+        .contains("connection closed before message completed")
+      {
+        return AppError::ServiceTemporaryUnavailable(error.to_string());
+      }
     }
+
+    // Handle request-related errors
+    if let Some(status_code) = error.status() {
+      if error.is_request() {
+        match status_code {
+          StatusCode::PAYLOAD_TOO_LARGE => {
+            return AppError::PayloadTooLarge(error.to_string());
+          },
+          status_code if status_code.is_server_error() => {
+            return AppError::ServiceTemporaryUnavailable(error.to_string());
+          },
+          _ => {
+            return AppError::InvalidRequest(error.to_string());
+          },
+        }
+      }
+    }
+
     AppError::Unhandled(error.to_string())
   }
 }
@@ -447,6 +467,7 @@ impl From<AIError> for AppError {
       AIError::PayloadTooLarge(err) => AppError::PayloadTooLarge(err),
       AIError::InvalidRequest(err) => AppError::InvalidRequest(err),
       AIError::SerdeError(err) => AppError::SerdeError(err),
+      AIError::ServiceUnavailable(err) => AppError::AIServiceUnavailable(err),
     }
   }
 }
diff --git a/libs/appflowy-ai-client/src/client.rs b/libs/appflowy-ai-client/src/client.rs
index 49457173e..8b9af236d 100644
--- a/libs/appflowy-ai-client/src/client.rs
+++ b/libs/appflowy-ai-client/src/client.rs
@@ -373,6 +373,11 @@ where
     resp: reqwest::Response,
   ) -> Result<impl Stream<Item = Result<Bytes, AIError>>, AIError> {
     let status_code = resp.status();
+    if status_code.is_server_error() {
+      let body = resp.text().await?;
+      return Err(AIError::ServiceUnavailable(body));
+    }
+
     if !status_code.is_success() {
       let body = resp.text().await?;
       return Err(AIError::InvalidRequest(body));
@@ -385,16 +390,29 @@ where
 }
 impl From<reqwest::Error> for AIError {
   fn from(error: reqwest::Error) -> Self {
+    if error.is_connect() {
+      return AIError::ServiceUnavailable(error.to_string());
+    }
+
     if error.is_timeout() {
       return AIError::RequestTimeout(error.to_string());
     }
 
-    if error.is_request() {
-      return if error.status() == Some(StatusCode::PAYLOAD_TOO_LARGE) {
-        AIError::PayloadTooLarge(error.to_string())
-      } else {
-        AIError::InvalidRequest(format!("{:?}", error))
-      };
+    // Handle request-related errors
+    if let Some(status_code) = error.status() {
+      if error.is_request() {
+        match status_code {
+          StatusCode::PAYLOAD_TOO_LARGE => {
+            return AIError::PayloadTooLarge(error.to_string());
+          },
+          status_code if status_code.is_server_error() => {
+            return AIError::ServiceUnavailable(error.to_string());
+          },
+          _ => {
+            return AIError::InvalidRequest(format!("{:?}", error));
+          },
+        }
+      }
     }
     AIError::Internal(error.into())
   }
diff --git a/libs/appflowy-ai-client/src/error.rs b/libs/appflowy-ai-client/src/error.rs
index d82520c62..c2f80a856 100644
--- a/libs/appflowy-ai-client/src/error.rs
+++ b/libs/appflowy-ai-client/src/error.rs
@@ -14,4 +14,7 @@ pub enum AIError {
 
   #[error(transparent)]
   SerdeError(#[from] serde_json::Error),
+
+  #[error("Service unavailable:{0}")]
+  ServiceUnavailable(String),
 }
diff --git a/libs/client-api/src/http_chat.rs b/libs/client-api/src/http_chat.rs
index dc5401217..9c09aa2c4 100644
--- a/libs/client-api/src/http_chat.rs
+++ b/libs/client-api/src/http_chat.rs
@@ -1,6 +1,7 @@
 use crate::http::log_request_id;
 use crate::Client;
 
+use app_error::AppError;
 use client_api_entity::chat_dto::{
   ChatMessage, CreateAnswerMessageParams, CreateChatMessageParams, CreateChatParams, MessageCursor,
   RepeatedChatMessage, UpdateChatMessageContentParams,
@@ -154,7 +155,17 @@ impl Client {
       .await?
       .timeout(Duration::from_secs(30))
       .send()
-      .await?;
+      .await
+      .map_err(|err| {
+        let app_err = AppError::from(err);
+        if matches!(app_err, AppError::ServiceTemporaryUnavailable(_)) {
+          AppError::AIServiceUnavailable(
+            "AI service temporarily unavailable, please try again later".to_string(),
+          )
+        } else {
+          app_err
+        }
+      })?;
     log_request_id(&resp);
     let stream = AppResponse::<serde_json::Value>::json_response_stream(resp).await?;
     Ok(QuestionStream::new(stream))
diff --git a/libs/shared-entity/src/response_stream.rs b/libs/shared-entity/src/response_stream.rs
index 034c4160b..aea8f6fa4 100644
--- a/libs/shared-entity/src/response_stream.rs
+++ b/libs/shared-entity/src/response_stream.rs
@@ -1,5 +1,5 @@
 use crate::response::{AppResponse, AppResponseError};
-use app_error::ErrorCode;
+use app_error::{AppError, ErrorCode};
 use bytes::{Buf, Bytes, BytesMut};
 use futures::{ready, Stream, TryStreamExt};
 
@@ -22,6 +22,11 @@ where
     resp: reqwest::Response,
   ) -> Result<impl Stream<Item = Result<T, AppResponseError>>, AppResponseError> {
     let status_code = resp.status();
+    if status_code.is_server_error() {
+      let body = resp.text().await?;
+      return Err(AppError::AIServiceUnavailable(body).into());
+    }
+
     if !status_code.is_success() {
       let body = resp.text().await?;
       return Err(AppResponseError::new(ErrorCode::Internal, body));
diff --git a/src/api/chat.rs b/src/api/chat.rs
index 67dc1fabc..62e465dba 100644
--- a/src/api/chat.rs
+++ b/src/api/chat.rs
@@ -316,7 +316,7 @@ async fn answer_stream_v2_handler(
       )
     },
     Err(err) => Ok(
-      HttpResponse::Ok()
+      HttpResponse::ServiceUnavailable()
         .content_type("text/event-stream")
         .streaming(stream::once(async move {
           Err(AppError::AIServiceUnavailable(err.to_string()))
diff --git a/src/biz/chat/ops.rs b/src/biz/chat/ops.rs
index ff6e2541a..d542e42f2 100644
--- a/src/biz/chat/ops.rs
+++ b/src/biz/chat/ops.rs
@@ -97,7 +97,8 @@ pub async fn generate_chat_message_answer(
       &ai_model,
       Some(metadata),
     )
-    .await?;
+    .await
+    .map_err(|err| AppError::AIServiceUnavailable(err.to_string()))?;
 
   info!("new_answer: {:?}", new_answer);
   // Save the answer to the database