feat: move chat messages to dedicated /chats/{id}/messages endpoint (#23021)

## Summary

Moves the messages response out of `GET /chats/{id}` and into a
dedicated `GET /chats/{id}/messages` endpoint.

### Backend
- `GET /chats/{id}` now returns just the `Chat` object (no messages)
- `GET /chats/{id}/messages` is a new endpoint returning
`ChatMessagesResponse` with `messages` and `queued_messages`
- Added `ChatMessagesResponse` SDK type and `GetChatMessages` client
method

### Frontend
- `getChat()` API method returns `Chat` instead of `ChatWithMessages`
- Added `getChatMessages()` API method for the new endpoint
- Split `chatQuery` into two: `chatQuery` (metadata) and
`chatMessagesQuery` (messages)
- Updated all cache mutations, optimistic updates, and websocket
handlers
- Updated tests and stories

### Files changed
| File | Change |
|---|---|
| `coderd/coderd.go` | Register `GET /messages` route |
| `coderd/chats.go` | Simplify `getChat`, add `getChatMessages` handler
|
| `codersdk/chats.go` | New type + method, update `GetChat` return |
| `site/src/api/api.ts` | New method, update `getChat` |
| `site/src/api/queries/chats.ts` | New query, update cache mutations |
| `site/src/pages/AgentsPage/AgentDetail.tsx` | Use separate queries |
| `site/src/pages/AgentsPage/AgentDetail/ChatContext.ts` | Update types
and cache writes |
| `site/src/pages/AgentsPage/AgentsPage.tsx` | Update websocket cache
handler |

coderd/chatd/chatd_test.go

@@ -176,7 +176,7 @@ func TestSubagentChatExcludesWorkspaceProvisioningTools(t *testing.T) {
 		if getErr != nil {
 			return false
 		}
-		if got.Chat.Status != codersdk.ChatStatusWaiting && got.Chat.Status != codersdk.ChatStatusError {
+		if got.Status != codersdk.ChatStatusWaiting && got.Status != codersdk.ChatStatusError {
 			return false
 		}
 		// Also ensure the subagent LLM call has been made.
@@ -1055,32 +1055,35 @@ func TestCreateWorkspaceTool_EndToEnd(t *testing.T) {
 	})
 	require.NoError(t, err)
 
-	var chatWithMessages codersdk.ChatWithMessages
+	var chatResult codersdk.Chat
 	require.Eventually(t, func() bool {
 		got, getErr := client.GetChat(ctx, chat.ID)
 		if getErr != nil {
 			return false
 		}
-		chatWithMessages = got
-		return got.Chat.Status == codersdk.ChatStatusWaiting || got.Chat.Status == codersdk.ChatStatusError
+		chatResult = got
+		return got.Status == codersdk.ChatStatusWaiting || got.Status == codersdk.ChatStatusError
 	}, testutil.WaitLong, testutil.IntervalFast)
 
-	if chatWithMessages.Chat.Status == codersdk.ChatStatusError {
+	if chatResult.Status == codersdk.ChatStatusError {
 		lastError := ""
-		if chatWithMessages.Chat.LastError != nil {
-			lastError = *chatWithMessages.Chat.LastError
+		if chatResult.LastError != nil {
+			lastError = *chatResult.LastError
 		}
 		require.FailNowf(t, "chat run failed", "last_error=%q", lastError)
 	}
 
-	require.NotNil(t, chatWithMessages.Chat.WorkspaceID)
-	workspaceID := *chatWithMessages.Chat.WorkspaceID
+	require.NotNil(t, chatResult.WorkspaceID)
+	workspaceID := *chatResult.WorkspaceID
 	workspace, err := client.Workspace(ctx, workspaceID)
 	require.NoError(t, err)
 	require.Equal(t, workspaceName, workspace.Name)
 
+	chatMsgs, err := client.GetChatMessages(ctx, chat.ID)
+	require.NoError(t, err)
+
 	var foundCreateWorkspaceResult bool
-	for _, message := range chatWithMessages.Messages {
+	for _, message := range chatMsgs.Messages {
 		if message.Role != "tool" {
 			continue
 		}
@@ -1223,33 +1226,36 @@ func TestStartWorkspaceTool_EndToEnd(t *testing.T) {
 	})
 	require.NoError(t, err)
 
-	var chatWithMessages codersdk.ChatWithMessages
+	var chatResult codersdk.Chat
 	require.Eventually(t, func() bool {
 		got, getErr := client.GetChat(ctx, chat.ID)
 		if getErr != nil {
 			return false
 		}
-		chatWithMessages = got
-		return got.Chat.Status == codersdk.ChatStatusWaiting || got.Chat.Status == codersdk.ChatStatusError
+		chatResult = got
+		return got.Status == codersdk.ChatStatusWaiting || got.Status == codersdk.ChatStatusError
 	}, testutil.WaitSuperLong, testutil.IntervalFast)
 
-	if chatWithMessages.Chat.Status == codersdk.ChatStatusError {
+	if chatResult.Status == codersdk.ChatStatusError {
 		lastError := ""
-		if chatWithMessages.Chat.LastError != nil {
-			lastError = *chatWithMessages.Chat.LastError
+		if chatResult.LastError != nil {
+			lastError = *chatResult.LastError
 		}
 		require.FailNowf(t, "chat run failed", "last_error=%q", lastError)
 	}
 
 	// Verify the workspace was started.
-	require.NotNil(t, chatWithMessages.Chat.WorkspaceID)
+	require.NotNil(t, chatResult.WorkspaceID)
 	updatedWorkspace, err := client.Workspace(ctx, workspace.ID)
 	require.NoError(t, err)
 	require.Equal(t, codersdk.WorkspaceTransitionStart, updatedWorkspace.LatestBuild.Transition)
 
+	chatMsgs, err := client.GetChatMessages(ctx, chat.ID)
+	require.NoError(t, err)
+
 	// Verify start_workspace tool result exists in the chat messages.
 	var foundStartWorkspaceResult bool
-	for _, message := range chatWithMessages.Messages {
+	for _, message := range chatMsgs.Messages {
 		if message.Role != "tool" {
 			continue
 		}

coderd/chatd/integration_test.go

@@ -92,17 +92,19 @@ func TestAnthropicWebSearchRoundTrip(t *testing.T) {
 	// Verify the chat completed and messages were persisted.
 	chatData, err := client.GetChat(ctx, chat.ID)
 	require.NoError(t, err)
+	chatMsgs, err := client.GetChatMessages(ctx, chat.ID)
+	require.NoError(t, err)
 	t.Logf("Chat status after step 1: %s, messages: %d",
-		chatData.Chat.Status, len(chatData.Messages))
-	logMessages(t, chatData.Messages)
+		chatData.Status, len(chatMsgs.Messages))
+	logMessages(t, chatMsgs.Messages)
 
-	require.Equal(t, codersdk.ChatStatusWaiting, chatData.Chat.Status,
+	require.Equal(t, codersdk.ChatStatusWaiting, chatData.Status,
 		"chat should be in waiting status after step 1")
 
 	// Find the first assistant message and verify it has the
 	// content parts the UI needs to render web search results:
 	// tool-call(PE), source, tool-result(PE), and text.
-	assistantMsg := findAssistantWithText(t, chatData.Messages)
+	assistantMsg := findAssistantWithText(t, chatMsgs.Messages)
 	require.NotNil(t, assistantMsg,
 		"expected an assistant message with text content after step 1")
 
@@ -152,17 +154,19 @@ func TestAnthropicWebSearchRoundTrip(t *testing.T) {
 	// Verify the follow-up completed and produced content.
 	chatData2, err := client.GetChat(ctx, chat.ID)
 	require.NoError(t, err)
+	chatMsgs2, err := client.GetChatMessages(ctx, chat.ID)
+	require.NoError(t, err)
 	t.Logf("Chat status after step 2: %s, messages: %d",
-		chatData2.Chat.Status, len(chatData2.Messages))
-	logMessages(t, chatData2.Messages)
+		chatData2.Status, len(chatMsgs2.Messages))
+	logMessages(t, chatMsgs2.Messages)
 
-	require.Equal(t, codersdk.ChatStatusWaiting, chatData2.Chat.Status,
+	require.Equal(t, codersdk.ChatStatusWaiting, chatData2.Status,
 		"chat should be in waiting status after step 2")
-	require.Greater(t, len(chatData2.Messages), len(chatData.Messages),
+	require.Greater(t, len(chatMsgs2.Messages), len(chatMsgs.Messages),
 		"follow-up should have added more messages")
 
 	// The last assistant message should have text.
-	lastAssistant := findLastAssistantWithText(t, chatData2.Messages)
+	lastAssistant := findLastAssistantWithText(t, chatMsgs2.Messages)
 	require.NotNil(t, lastAssistant,
 		"expected an assistant message with text in the follow-up")
 

coderd/chats.go

@@ -360,6 +360,15 @@ func (api *API) listChatModels(rw http.ResponseWriter, r *http.Request) {
 //
 //nolint:revive // HTTP handler writes to ResponseWriter.
 func (api *API) getChat(rw http.ResponseWriter, r *http.Request) {
+	ctx := r.Context()
+	chat := httpmw.ChatParam(r)
+	httpapi.Write(ctx, rw, http.StatusOK, convertChat(chat, nil))
+}
+
+// EXPERIMENTAL: this endpoint is experimental and is subject to change.
+//
+//nolint:revive // HTTP handler writes to ResponseWriter.
+func (api *API) getChatMessages(rw http.ResponseWriter, r *http.Request) {
 	ctx := r.Context()
 	chat := httpmw.ChatParam(r)
 	chatID := chat.ID
@@ -385,8 +394,7 @@ func (api *API) getChat(rw http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	httpapi.Write(ctx, rw, http.StatusOK, codersdk.ChatWithMessages{
-		Chat:           convertChat(chat, nil),
+	httpapi.Write(ctx, rw, http.StatusOK, codersdk.ChatMessagesResponse{
 		Messages:       convertChatMessages(messages),
 		QueuedMessages: convertChatQueuedMessages(queuedMessages),
 	})

coderd/chats_test.go

@@ -85,12 +85,14 @@ func TestPostChats(t *testing.T) {
 		require.NotNil(t, chat.RootChatID)
 		require.Equal(t, chat.ID, *chat.RootChatID)
 
-		chatWithMessages, err := client.GetChat(ctx, chat.ID)
+		chatResult, err := client.GetChat(ctx, chat.ID)
 		require.NoError(t, err)
-		require.Equal(t, chat.ID, chatWithMessages.Chat.ID)
+		messagesResult, err := client.GetChatMessages(ctx, chat.ID)
+		require.NoError(t, err)
+		require.Equal(t, chat.ID, chatResult.ID)
 
 		foundUserMessage := false
-		for _, message := range chatWithMessages.Messages {
+		for _, message := range messagesResult.Messages {
 			if message.Role != "user" {
 				continue
 			}
@@ -123,9 +125,9 @@ func TestPostChats(t *testing.T) {
 		})
 		require.NoError(t, err)
 
-		chatWithMessages, err := client.GetChat(ctx, chat.ID)
+		messagesResult, err := client.GetChatMessages(ctx, chat.ID)
 		require.NoError(t, err)
-		for _, message := range chatWithMessages.Messages {
+		for _, message := range messagesResult.Messages {
 			require.NotEqual(t, "system", message.Role)
 		}
 	})
@@ -1322,19 +1324,21 @@ func TestGetChat(t *testing.T) {
 		})
 		require.NoError(t, err)
 
-		chatWithMessages, err := client.GetChat(ctx, createdChat.ID)
+		chatResult, err := client.GetChat(ctx, createdChat.ID)
 		require.NoError(t, err)
-		require.Equal(t, createdChat.ID, chatWithMessages.Chat.ID)
-		require.Equal(t, firstUser.UserID, chatWithMessages.Chat.OwnerID)
-		require.Equal(t, modelConfig.ID, chatWithMessages.Chat.LastModelConfigID)
-		require.Equal(t, "get chat route payload", chatWithMessages.Chat.Title)
-		require.NotZero(t, chatWithMessages.Chat.CreatedAt)
-		require.NotZero(t, chatWithMessages.Chat.UpdatedAt)
-		require.NotEmpty(t, chatWithMessages.Messages)
-		require.Empty(t, chatWithMessages.QueuedMessages)
+		messagesResult, err := client.GetChatMessages(ctx, createdChat.ID)
+		require.NoError(t, err)
+		require.Equal(t, createdChat.ID, chatResult.ID)
+		require.Equal(t, firstUser.UserID, chatResult.OwnerID)
+		require.Equal(t, modelConfig.ID, chatResult.LastModelConfigID)
+		require.Equal(t, "get chat route payload", chatResult.Title)
+		require.NotZero(t, chatResult.CreatedAt)
+		require.NotZero(t, chatResult.UpdatedAt)
+		require.NotEmpty(t, messagesResult.Messages)
+		require.Empty(t, messagesResult.QueuedMessages)
 
 		foundUserMessage := false
-		for _, message := range chatWithMessages.Messages {
+		for _, message := range messagesResult.Messages {
 			require.Equal(t, createdChat.ID, message.ChatID)
 			require.NotEqual(t, "system", message.Role)
 			for _, part := range message.Content {
@@ -1646,19 +1650,19 @@ func TestPostChatMessages(t *testing.T) {
 			require.True(t, hasTextPart(created.QueuedMessage.Content, messageText))
 
 			require.Eventually(t, func() bool {
-				chatWithMessages, getErr := client.GetChat(ctx, chat.ID)
+				messagesResult, getErr := client.GetChatMessages(ctx, chat.ID)
 				if getErr != nil {
 					return false
 				}
 
-				for _, queued := range chatWithMessages.QueuedMessages {
+				for _, queued := range messagesResult.QueuedMessages {
 					if queued.ID == created.QueuedMessage.ID &&
 						queued.ChatID == chat.ID &&
 						hasTextPart(queued.Content, messageText) {
 						return true
 					}
 				}
-				for _, message := range chatWithMessages.Messages {
+				for _, message := range messagesResult.Messages {
 					if message.Role == "user" && hasTextPart(message.Content, messageText) {
 						return true
 					}
@@ -1674,11 +1678,11 @@ func TestPostChatMessages(t *testing.T) {
 			require.True(t, hasTextPart(created.Message.Content, messageText))
 
 			require.Eventually(t, func() bool {
-				chatWithMessages, getErr := client.GetChat(ctx, chat.ID)
+				messagesResult, getErr := client.GetChatMessages(ctx, chat.ID)
 				if getErr != nil {
 					return false
 				}
-				for _, message := range chatWithMessages.Messages {
+				for _, message := range messagesResult.Messages {
 					if message.ID == created.Message.ID &&
 						message.Role == "user" &&
 						hasTextPart(message.Content, messageText) {
@@ -1784,11 +1788,11 @@ func TestChatMessageWithFileReferences(t *testing.T) {
 
 		var found bool
 		require.Eventually(t, func() bool {
-			chatWithMessages, getErr := client.GetChat(ctx, chat.ID)
+			messagesResult, getErr := client.GetChatMessages(ctx, chat.ID)
 			if getErr != nil {
 				return false
 			}
-			for _, message := range chatWithMessages.Messages {
+			for _, message := range messagesResult.Messages {
 				if message.Role != "user" {
 					continue
 				}
@@ -1802,7 +1806,7 @@ func TestChatMessageWithFileReferences(t *testing.T) {
 			}
 			// The message may have been queued.
 			if created.Queued && created.QueuedMessage != nil {
-				for _, queued := range chatWithMessages.QueuedMessages {
+				for _, queued := range messagesResult.QueuedMessages {
 					for _, part := range queued.Content {
 						if part.Type == codersdk.ChatMessagePartTypeText &&
 							part.Text == wantText {
@@ -1842,11 +1846,11 @@ func TestChatMessageWithFileReferences(t *testing.T) {
 			"```lib/utils.ts\nconst x = 1;\n```"
 
 		require.Eventually(t, func() bool {
-			chatWithMessages, getErr := client.GetChat(ctx, chat.ID)
+			messagesResult, getErr := client.GetChatMessages(ctx, chat.ID)
 			if getErr != nil {
 				return false
 			}
-			for _, msg := range chatWithMessages.Messages {
+			for _, msg := range messagesResult.Messages {
 				for _, part := range msg.Content {
 					if part.Type == codersdk.ChatMessagePartTypeText && part.Text == wantText {
 						return true
@@ -1854,7 +1858,7 @@ func TestChatMessageWithFileReferences(t *testing.T) {
 				}
 			}
 			if created.Queued && created.QueuedMessage != nil {
-				for _, queued := range chatWithMessages.QueuedMessages {
+				for _, queued := range messagesResult.QueuedMessages {
 					for _, part := range queued.Content {
 						if part.Type == codersdk.ChatMessagePartTypeText && part.Text == wantText {
 							return true
@@ -1889,11 +1893,11 @@ func TestChatMessageWithFileReferences(t *testing.T) {
 		// No fenced code block when content is empty.
 		wantText := "[file-reference] README.md:1"
 		require.Eventually(t, func() bool {
-			chatWithMessages, getErr := client.GetChat(ctx, chat.ID)
+			messagesResult, getErr := client.GetChatMessages(ctx, chat.ID)
 			if getErr != nil {
 				return false
 			}
-			for _, msg := range chatWithMessages.Messages {
+			for _, msg := range messagesResult.Messages {
 				for _, part := range msg.Content {
 					if part.Type == codersdk.ChatMessagePartTypeText && part.Text == wantText {
 						return true
@@ -1901,7 +1905,7 @@ func TestChatMessageWithFileReferences(t *testing.T) {
 				}
 			}
 			if created.Queued && created.QueuedMessage != nil {
-				for _, queued := range chatWithMessages.QueuedMessages {
+				for _, queued := range messagesResult.QueuedMessages {
 					for _, part := range queued.Content {
 						if part.Type == codersdk.ChatMessagePartTypeText && part.Text == wantText {
 							return true
@@ -1937,11 +1941,11 @@ func TestChatMessageWithFileReferences(t *testing.T) {
 			"```server.go\nfunc main() {\n\tfmt.Println()\n}\n```"
 
 		require.Eventually(t, func() bool {
-			chatWithMessages, getErr := client.GetChat(ctx, chat.ID)
+			messagesResult, getErr := client.GetChatMessages(ctx, chat.ID)
 			if getErr != nil {
 				return false
 			}
-			for _, msg := range chatWithMessages.Messages {
+			for _, msg := range messagesResult.Messages {
 				for _, part := range msg.Content {
 					if part.Type == codersdk.ChatMessagePartTypeText && part.Text == wantText {
 						return true
@@ -1949,7 +1953,7 @@ func TestChatMessageWithFileReferences(t *testing.T) {
 				}
 			}
 			if created.Queued && created.QueuedMessage != nil {
-				for _, queued := range chatWithMessages.QueuedMessages {
+				for _, queued := range messagesResult.QueuedMessages {
 					for _, part := range queued.Content {
 						if part.Type == codersdk.ChatMessagePartTypeText && part.Text == wantText {
 							return true
@@ -2017,7 +2021,7 @@ func TestChatMessageWithFileReferences(t *testing.T) {
 		}
 
 		require.Eventually(t, func() bool {
-			chatWithMessages, getErr := client.GetChat(ctx, chat.ID)
+			messagesResult, getErr := client.GetChatMessages(ctx, chat.ID)
 			if getErr != nil {
 				return false
 			}
@@ -2042,13 +2046,13 @@ func TestChatMessageWithFileReferences(t *testing.T) {
 				return true
 			}
 
-			for _, msg := range chatWithMessages.Messages {
+			for _, msg := range messagesResult.Messages {
 				if msg.Role == "user" && checkParts(msg.Content) {
 					return true
 				}
 			}
 			if created.Queued && created.QueuedMessage != nil {
-				for _, queued := range chatWithMessages.QueuedMessages {
+				for _, queued := range messagesResult.QueuedMessages {
 					if checkParts(queued.Content) {
 						return true
 					}
@@ -2201,9 +2205,9 @@ func TestChatMessageWithFiles(t *testing.T) {
 		}
 
 		// Verify file parts omit inline data in the API response.
-		chatWithMessages, err := client.GetChat(ctx, chat.ID)
+		messagesResult, err := client.GetChatMessages(ctx, chat.ID)
 		require.NoError(t, err)
-		for _, msg := range chatWithMessages.Messages {
+		for _, msg := range messagesResult.Messages {
 			for _, part := range msg.Content {
 				if part.Type == codersdk.ChatMessagePartTypeFile {
 					require.True(t, part.FileID.Valid, "file part should have a valid file_id")
@@ -2297,11 +2301,11 @@ func TestPatchChatMessage(t *testing.T) {
 		})
 		require.NoError(t, err)
 
-		chatWithMessages, err := client.GetChat(ctx, chat.ID)
+		messagesResult, err := client.GetChatMessages(ctx, chat.ID)
 		require.NoError(t, err)
 
 		var userMessageID int64
-		for _, message := range chatWithMessages.Messages {
+		for _, message := range messagesResult.Messages {
 			if message.Role == "user" {
 				userMessageID = message.ID
 				break
@@ -2329,11 +2333,11 @@ func TestPatchChatMessage(t *testing.T) {
 		}
 		require.True(t, foundEditedText)
 
-		updatedChat, err := client.GetChat(ctx, chat.ID)
+		messagesResult, err = client.GetChatMessages(ctx, chat.ID)
 		require.NoError(t, err)
 		foundEditedInChat := false
 		foundOriginalInChat := false
-		for _, message := range updatedChat.Messages {
+		for _, message := range messagesResult.Messages {
 			if message.Role != "user" {
 				continue
 			}
@@ -2382,11 +2386,11 @@ func TestPatchChatMessage(t *testing.T) {
 		require.NoError(t, err)
 
 		// Find the user message ID.
-		chatWithMessages, err := client.GetChat(ctx, chat.ID)
+		messagesResult, err := client.GetChatMessages(ctx, chat.ID)
 		require.NoError(t, err)
 
 		var userMessageID int64
-		for _, message := range chatWithMessages.Messages {
+		for _, message := range messagesResult.Messages {
 			if message.Role == "user" {
 				userMessageID = message.ID
 				break
@@ -2424,12 +2428,12 @@ func TestPatchChatMessage(t *testing.T) {
 		require.True(t, foundText, "edited message should contain updated text")
 		require.True(t, foundFile, "edited message should preserve file_id")
 
-		// GET the chat and verify the file_id persists.
-		updatedChat, err := client.GetChat(ctx, chat.ID)
+		// GET the chat messages and verify the file_id persists.
+		messagesResult, err = client.GetChatMessages(ctx, chat.ID)
 		require.NoError(t, err)
 
 		var foundTextInChat, foundFileInChat bool
-		for _, message := range updatedChat.Messages {
+		for _, message := range messagesResult.Messages {
 			if message.Role != "user" {
 				continue
 			}
@@ -3037,9 +3041,9 @@ func TestDeleteChatQueuedMessage(t *testing.T) {
 		res.Body.Close()
 		require.Equal(t, http.StatusNoContent, res.StatusCode)
 
-		chatWithMessages, err := client.GetChat(ctx, chat.ID)
+		messagesResult, err := client.GetChatMessages(ctx, chat.ID)
 		require.NoError(t, err)
-		for _, queued := range chatWithMessages.QueuedMessages {
+		for _, queued := range messagesResult.QueuedMessages {
 			require.NotEqual(t, queuedMessage.ID, queued.ID)
 		}
 
@@ -3136,9 +3140,9 @@ func TestPromoteChatQueuedMessage(t *testing.T) {
 		}
 		require.True(t, foundPromotedText)
 
-		chatWithMessages, err := client.GetChat(ctx, chat.ID)
+		messagesResult, err := client.GetChatMessages(ctx, chat.ID)
 		require.NoError(t, err)
-		for _, queued := range chatWithMessages.QueuedMessages {
+		for _, queued := range messagesResult.QueuedMessages {
 			require.NotEqual(t, queuedMessage.ID, queued.ID)
 		}
 

coderd/coderd.go

@@ -1173,6 +1173,7 @@ func New(options *Options) *API {
 				r.Get("/git/watch", api.watchChatGit)
 				r.Post("/archive", api.archiveChat)
 				r.Post("/unarchive", api.unarchiveChat)
+				r.Get("/messages", api.getChatMessages)
 				r.Post("/messages", api.postChatMessages)
 				r.Patch("/messages/{message}", api.patchChatMessage)
 				r.Get("/stream", api.streamChat)

codersdk/chats.go

@@ -167,9 +167,8 @@ type UploadChatFileResponse struct {
 	ID uuid.UUID `json:"id" format:"uuid"`
 }
 
-// ChatWithMessages is a chat along with its messages.
-type ChatWithMessages struct {
-	Chat           Chat                `json:"chat"`
+// ChatMessagesResponse contains the messages and queued messages for a chat.
+type ChatMessagesResponse struct {
 	Messages       []ChatMessage       `json:"messages"`
 	QueuedMessages []ChatQueuedMessage `json:"queued_messages"`
 }
@@ -980,20 +979,34 @@ func (c *Client) StreamChat(ctx context.Context, chatID uuid.UUID, opts *StreamC
 	}), nil
 }
 
-// GetChat returns a chat by ID, including its messages.
-func (c *Client) GetChat(ctx context.Context, chatID uuid.UUID) (ChatWithMessages, error) {
+// GetChat returns a chat by ID.
+func (c *Client) GetChat(ctx context.Context, chatID uuid.UUID) (Chat, error) {
 	res, err := c.Request(ctx, http.MethodGet, fmt.Sprintf("/api/experimental/chats/%s", chatID), nil)
 	if err != nil {
-		return ChatWithMessages{}, err
+		return Chat{}, err
 	}
 	defer res.Body.Close()
 	if res.StatusCode != http.StatusOK {
-		return ChatWithMessages{}, ReadBodyAsError(res)
+		return Chat{}, ReadBodyAsError(res)
 	}
-	var chat ChatWithMessages
+	var chat Chat
 	return chat, json.NewDecoder(res.Body).Decode(&chat)
 }
 
+// GetChatMessages returns the messages and queued messages for a chat.
+func (c *Client) GetChatMessages(ctx context.Context, chatID uuid.UUID) (ChatMessagesResponse, error) {
+	res, err := c.Request(ctx, http.MethodGet, fmt.Sprintf("/api/experimental/chats/%s/messages", chatID), nil)
+	if err != nil {
+		return ChatMessagesResponse{}, err
+	}
+	defer res.Body.Close()
+	if res.StatusCode != http.StatusOK {
+		return ChatMessagesResponse{}, ReadBodyAsError(res)
+	}
+	var resp ChatMessagesResponse
+	return resp, json.NewDecoder(res.Body).Decode(&resp)
+}
+
 func (c *Client) ArchiveChat(ctx context.Context, chatID uuid.UUID) error {
 	res, err := c.Request(ctx, http.MethodPost, fmt.Sprintf("/api/experimental/chats/%s/archive", chatID), nil)
 	if err != nil {

site/src/api/api.ts

@@ -2948,12 +2948,20 @@ class ApiMethods {
 		);
 		return response.data;
 	};
-	getChat = async (chatId: string): Promise<TypesGen.ChatWithMessages> => {
-		const response = await this.axios.get<TypesGen.ChatWithMessages>(
+	getChat = async (chatId: string): Promise<TypesGen.Chat> => {
+		const response = await this.axios.get<TypesGen.Chat>(
 			`/api/experimental/chats/${chatId}`,
 		);
 		return response.data;
 	};
+	getChatMessages = async (
+		chatId: string,
+	): Promise<TypesGen.ChatMessagesResponse> => {
+		const response = await this.axios.get<TypesGen.ChatMessagesResponse>(
+			`/api/experimental/chats/${chatId}/messages`,
+		);
+		return response.data;
+	};
 
 	createChat = async (
 		req: TypesGen.CreateChatRequest,

site/src/api/queries/chats.test.ts

@@ -55,15 +55,6 @@ const makeChat = (
 	...overrides,
 });
 
-const makeChatWithMessages = (
-	chatId: string,
-	overrides?: Partial<TypesGen.Chat>,
-): TypesGen.ChatWithMessages => ({
-	chat: makeChat(chatId, overrides),
-	messages: [],
-	queued_messages: [],
-});
-
 const createTestQueryClient = (): QueryClient =>
 	new QueryClient({
 		defaultOptions: {
@@ -99,17 +90,15 @@ describe("archiveChat optimistic update", () => {
 		const queryClient = createTestQueryClient();
 		const chatId = "chat-1";
 		seedInfiniteChats(queryClient, [makeChat(chatId)]);
-		queryClient.setQueryData(chatKey(chatId), makeChatWithMessages(chatId));
+		queryClient.setQueryData(chatKey(chatId), makeChat(chatId));
 
 		vi.mocked(API.archiveChat).mockResolvedValue();
 
 		const mutation = archiveChat(queryClient);
 		await mutation.onMutate(chatId);
 
-		const cachedChat = queryClient.getQueryData<TypesGen.ChatWithMessages>(
-			chatKey(chatId),
-		);
-		expect(cachedChat?.chat.archived).toBe(true);
+		const cachedChat = queryClient.getQueryData<TypesGen.Chat>(chatKey(chatId));
+		expect(cachedChat?.archived).toBe(true);
 	});
 
 	it("rolls back the chats list on error by invalidating", async () => {
@@ -117,7 +106,7 @@ describe("archiveChat optimistic update", () => {
 		const chatId = "chat-1";
 		const initialChats = [makeChat(chatId)];
 		seedInfiniteChats(queryClient, initialChats);
-		queryClient.setQueryData(chatKey(chatId), makeChatWithMessages(chatId));
+		queryClient.setQueryData(chatKey(chatId), makeChat(chatId));
 		const invalidateSpy = vi.spyOn(queryClient, "invalidateQueries");
 
 		const mutation = archiveChat(queryClient);
@@ -139,22 +128,19 @@ describe("archiveChat optimistic update", () => {
 		const queryClient = createTestQueryClient();
 		const chatId = "chat-1";
 		seedInfiniteChats(queryClient, [makeChat(chatId)]);
-		queryClient.setQueryData(chatKey(chatId), makeChatWithMessages(chatId));
+		queryClient.setQueryData(chatKey(chatId), makeChat(chatId));
 
 		const mutation = archiveChat(queryClient);
 		const context = await mutation.onMutate(chatId);
 
 		expect(
-			queryClient.getQueryData<TypesGen.ChatWithMessages>(chatKey(chatId))?.chat
-				.archived,
+			queryClient.getQueryData<TypesGen.Chat>(chatKey(chatId))?.archived,
 		).toBe(true);
 
 		mutation.onError(new Error("server error"), chatId, context);
 
-		const rolledBack = queryClient.getQueryData<TypesGen.ChatWithMessages>(
-			chatKey(chatId),
-		);
-		expect(rolledBack?.chat.archived).toBe(false);
+		const rolledBack = queryClient.getQueryData<TypesGen.Chat>(chatKey(chatId));
+		expect(rolledBack?.archived).toBe(false);
 	});
 
 	it("handles error rollback gracefully when context is undefined", () => {
@@ -226,15 +212,14 @@ describe("unarchiveChat optimistic update", () => {
 		seedInfiniteChats(queryClient, [makeChat(chatId, { archived: true })]);
 		queryClient.setQueryData(
 			chatKey(chatId),
-			makeChatWithMessages(chatId, { archived: true }),
+			makeChat(chatId, { archived: true }),
 		);
 
 		const mutation = unarchiveChat(queryClient);
 		await mutation.onMutate(chatId);
 
 		expect(
-			queryClient.getQueryData<TypesGen.ChatWithMessages>(chatKey(chatId))?.chat
-				.archived,
+			queryClient.getQueryData<TypesGen.Chat>(chatKey(chatId))?.archived,
 		).toBe(false);
 	});
 
@@ -244,7 +229,7 @@ describe("unarchiveChat optimistic update", () => {
 		seedInfiniteChats(queryClient, [makeChat(chatId, { archived: true })]);
 		queryClient.setQueryData(
 			chatKey(chatId),
-			makeChatWithMessages(chatId, { archived: true }),
+			makeChat(chatId, { archived: true }),
 		);
 		const invalidateSpy = vi.spyOn(queryClient, "invalidateQueries");
 
@@ -254,8 +239,7 @@ describe("unarchiveChat optimistic update", () => {
 		// Verify optimistic update.
 		expect(readInfiniteChats(queryClient)?.[0].archived).toBe(false);
 		expect(
-			queryClient.getQueryData<TypesGen.ChatWithMessages>(chatKey(chatId))?.chat
-				.archived,
+			queryClient.getQueryData<TypesGen.Chat>(chatKey(chatId))?.archived,
 		).toBe(false);
 
 		// Roll back.
@@ -267,8 +251,7 @@ describe("unarchiveChat optimistic update", () => {
 		});
 		// The individual chat cache is restored directly.
 		expect(
-			queryClient.getQueryData<TypesGen.ChatWithMessages>(chatKey(chatId))?.chat
-				.archived,
+			queryClient.getQueryData<TypesGen.Chat>(chatKey(chatId))?.archived,
 		).toBe(true);
 	});
 

site/src/api/queries/chats.ts

@@ -4,6 +4,8 @@ import type { QueryClient, UseInfiniteQueryOptions } from "react-query";
 
 export const chatsKey = ["chats"] as const;
 export const chatKey = (chatId: string) => ["chats", chatId] as const;
+export const chatMessagesKey = (chatId: string) =>
+	["chats", chatId, "messages"] as const;
 
 /**
  * Updates a single chat inside every page of the infinite chats query
@@ -96,12 +98,17 @@ export const chat = (chatId: string) => ({
 	queryFn: () => API.getChat(chatId),
 });
 
+export const chatMessages = (chatId: string) => ({
+	queryKey: chatMessagesKey(chatId),
+	queryFn: () => API.getChatMessages(chatId),
+});
+
 export const archiveChat = (queryClient: QueryClient) => ({
 	mutationFn: (chatId: string) => API.archiveChat(chatId),
 	onMutate: async (chatId: string) => {
 		await queryClient.cancelQueries({ queryKey: chatsKey });
 		await queryClient.cancelQueries({ queryKey: chatKey(chatId) });
-		const previousChat = queryClient.getQueryData<TypesGen.ChatWithMessages>(
+		const previousChat = queryClient.getQueryData<TypesGen.Chat>(
 			chatKey(chatId),
 		);
 		updateInfiniteChatsCache(queryClient, (chats) =>
@@ -110,9 +117,9 @@ export const archiveChat = (queryClient: QueryClient) => ({
 			),
 		);
 		if (previousChat) {
-			queryClient.setQueryData<TypesGen.ChatWithMessages>(chatKey(chatId), {
+			queryClient.setQueryData<TypesGen.Chat>(chatKey(chatId), {
 				...previousChat,
-				chat: { ...previousChat.chat, archived: true },
+				archived: true,
 			});
 		}
 		return { previousChat };
@@ -122,14 +129,14 @@ export const archiveChat = (queryClient: QueryClient) => ({
 		chatId: string,
 		context:
 			| {
-					previousChat?: TypesGen.ChatWithMessages;
+					previousChat?: TypesGen.Chat;
 			  }
 			| undefined,
 	) => {
 		// Rollback: invalidate to re-fetch the correct state.
 		void queryClient.invalidateQueries({ queryKey: chatsKey });
 		if (context?.previousChat) {
-			queryClient.setQueryData<TypesGen.ChatWithMessages>(
+			queryClient.setQueryData<TypesGen.Chat>(
 				chatKey(chatId),
 				context.previousChat,
 			);
@@ -146,7 +153,7 @@ export const unarchiveChat = (queryClient: QueryClient) => ({
 	onMutate: async (chatId: string) => {
 		await queryClient.cancelQueries({ queryKey: chatsKey });
 		await queryClient.cancelQueries({ queryKey: chatKey(chatId) });
-		const previousChat = queryClient.getQueryData<TypesGen.ChatWithMessages>(
+		const previousChat = queryClient.getQueryData<TypesGen.Chat>(
 			chatKey(chatId),
 		);
 		updateInfiniteChatsCache(queryClient, (chats) =>
@@ -155,9 +162,9 @@ export const unarchiveChat = (queryClient: QueryClient) => ({
 			),
 		);
 		if (previousChat) {
-			queryClient.setQueryData<TypesGen.ChatWithMessages>(chatKey(chatId), {
+			queryClient.setQueryData<TypesGen.Chat>(chatKey(chatId), {
 				...previousChat,
-				chat: { ...previousChat.chat, archived: false },
+				archived: false,
 			});
 		}
 		return { previousChat };
@@ -167,14 +174,14 @@ export const unarchiveChat = (queryClient: QueryClient) => ({
 		chatId: string,
 		context:
 			| {
-					previousChat?: TypesGen.ChatWithMessages;
+					previousChat?: TypesGen.Chat;
 			  }
 			| undefined,
 	) => {
 		// Rollback: invalidate to re-fetch the correct state.
 		void queryClient.invalidateQueries({ queryKey: chatsKey });
 		if (context?.previousChat) {
-			queryClient.setQueryData<TypesGen.ChatWithMessages>(
+			queryClient.setQueryData<TypesGen.Chat>(
 				chatKey(chatId),
 				context.previousChat,
 			);
@@ -215,6 +222,7 @@ export const editChatMessage = (queryClient: QueryClient, chatId: string) => ({
 	onSuccess: () => {
 		void queryClient.invalidateQueries({ queryKey: chatsKey });
 		void queryClient.invalidateQueries({ queryKey: chatKey(chatId) });
+		void queryClient.invalidateQueries({ queryKey: chatMessagesKey(chatId) });
 	},
 });
 
@@ -233,6 +241,7 @@ export const deleteChatQueuedMessage = (
 		API.deleteChatQueuedMessage(chatId, queuedMessageId),
 	onSuccess: async () => {
 		await queryClient.invalidateQueries({ queryKey: chatKey(chatId) });
+		await queryClient.invalidateQueries({ queryKey: chatMessagesKey(chatId) });
 	},
 });
 
@@ -245,6 +254,7 @@ export const promoteChatQueuedMessage = (
 	onSuccess: () => {
 		void queryClient.invalidateQueries({ queryKey: chatsKey });
 		void queryClient.invalidateQueries({ queryKey: chatKey(chatId) });
+		void queryClient.invalidateQueries({ queryKey: chatMessagesKey(chatId) });
 	},
 });
 

site/src/api/typesGenerated.ts

@@ -1229,6 +1229,15 @@ export interface ChatMessageUsage {
 	readonly context_limit?: number;
 }
 
+// From codersdk/chats.go
+/**
+ * ChatMessagesResponse contains the messages and queued messages for a chat.
+ */
+export interface ChatMessagesResponse {
+	readonly messages: readonly ChatMessage[];
+	readonly queued_messages: readonly ChatQueuedMessage[];
+}
+
 // From codersdk/chats.go
 /**
  * ChatModel represents a model in the chat model catalog.
@@ -1631,16 +1640,6 @@ export interface ChatSystemPromptResponse {
 	readonly system_prompt: string;
 }
 
-// From codersdk/chats.go
-/**
- * ChatWithMessages is a chat along with its messages.
- */
-export interface ChatWithMessages {
-	readonly chat: Chat;
-	readonly messages: readonly ChatMessage[];
-	readonly queued_messages: readonly ChatQueuedMessage[];
-}
-
 // From codersdk/client.go
 /**
  * CoderDesktopTelemetryHeader contains a JSON-encoded representation of Desktop telemetry

site/src/pages/AgentsPage/AgentDetail.stories.tsx

@@ -15,6 +15,7 @@ import {
 	chatDiffContentsKey,
 	chatDiffStatusKey,
 	chatKey,
+	chatMessagesKey,
 	chatModelsKey,
 	chatsKey,
 } from "api/queries/chats";
@@ -131,13 +132,15 @@ index abc1234..def5678 100644
  }
 `;
 
-/** Build `parameters.queries` entries for a given chat data object. */
+/** Build `parameters.queries` entries for a given chat and messages. */
 const buildQueries = (
-	chatData: TypesGen.ChatWithMessages,
+	chat: TypesGen.Chat,
+	messagesData: TypesGen.ChatMessagesResponse,
 	opts?: { diffUrl?: string },
 ) => [
-	{ key: chatKey(CHAT_ID), data: chatData },
-	{ key: chatsKey, data: [chatData.chat] },
+	{ key: chatKey(CHAT_ID), data: chat },
+	{ key: chatMessagesKey(CHAT_ID), data: messagesData },
+	{ key: chatsKey, data: [chat] },
 	{
 		key: chatDiffStatusKey(CHAT_ID),
 		data: {
@@ -217,12 +220,12 @@ export const WithMessageHistory: Story = {
 	parameters: {
 		queries: buildQueries(
 			{
-				chat: {
-					id: CHAT_ID,
-					...baseChatFields,
-					title: "Markdown rendering showcase",
-					status: "completed",
-				},
+				id: CHAT_ID,
+				...baseChatFields,
+				title: "Markdown rendering showcase",
+				status: "completed",
+			},
+			{
 				messages: [
 					// -- Turn 1: user asks for a summary --
 					{
@@ -533,8 +536,8 @@ export const WithMessageHistory: Story = {
 	},
 };
 
-/** Skeleton placeholder when no query data is available yet. */
-export const Loading: Story = {};
+/** Skeleton placeholder when no query data is available yet. */ export const Loading: Story =
+	{};
 
 /** Full layout with actions menu and diff panel portaled to the right slot. */
 export const CompletedWithDiffPanel: Story = {
@@ -545,15 +548,12 @@ export const CompletedWithDiffPanel: Story = {
 	parameters: {
 		queries: buildQueries(
 			{
-				chat: {
-					id: CHAT_ID,
-					...baseChatFields,
-					title: "Build a feature",
-					status: "completed",
-				},
-				messages: [],
-				queued_messages: [],
+				id: CHAT_ID,
+				...baseChatFields,
+				title: "Build a feature",
+				status: "completed",
 			},
+			{ messages: [], queued_messages: [] },
 			{ diffUrl: "https://github.com/coder/coder/pull/123" },
 		),
 	},
@@ -583,15 +583,12 @@ export const NoDiffUrl: Story = {
 	parameters: {
 		queries: buildQueries(
 			{
-				chat: {
-					id: CHAT_ID,
-					...baseChatFields,
-					title: "No diff yet",
-					status: "completed",
-				},
-				messages: [],
-				queued_messages: [],
+				id: CHAT_ID,
+				...baseChatFields,
+				title: "No diff yet",
+				status: "completed",
 			},
+			{ messages: [], queued_messages: [] },
 			{ diffUrl: undefined },
 		),
 	},
@@ -602,12 +599,12 @@ export const WithSubagentCards: Story = {
 	parameters: {
 		queries: buildQueries(
 			{
-				chat: {
-					id: CHAT_ID,
-					...baseChatFields,
-					title: "Parent agent",
-					status: "running",
-				},
+				id: CHAT_ID,
+				...baseChatFields,
+				title: "Parent agent",
+				status: "running",
+			},
+			{
 				messages: [
 					{
 						id: 1,
@@ -654,12 +651,12 @@ export const WithReasoningCollapsed: Story = {
 	parameters: {
 		queries: buildQueries(
 			{
-				chat: {
-					id: CHAT_ID,
-					...baseChatFields,
-					title: "Reasoning title",
-					status: "completed",
-				},
+				id: CHAT_ID,
+				...baseChatFields,
+				title: "Reasoning title",
+				status: "completed",
+			},
+			{
 				messages: [
 					{
 						id: 1,
@@ -706,15 +703,12 @@ export const StreamedSubagentTitle: Story = {
 	parameters: {
 		queries: buildQueries(
 			{
-				chat: {
-					id: CHAT_ID,
-					...baseChatFields,
-					title: "Streaming title",
-					status: "running",
-				},
-				messages: [],
-				queued_messages: [],
+				id: CHAT_ID,
+				...baseChatFields,
+				title: "Streaming title",
+				status: "running",
 			},
+			{ messages: [], queued_messages: [] },
 			{ diffUrl: undefined },
 		),
 		webSocket: {
@@ -761,15 +755,12 @@ export const SidebarWithPRAndRepos: Story = {
 	parameters: {
 		queries: buildQueries(
 			{
-				chat: {
-					id: CHAT_ID,
-					...baseChatFields,
-					title: "Full sidebar demo",
-					status: "completed",
-				},
-				messages: [],
-				queued_messages: [],
+				id: CHAT_ID,
+				...baseChatFields,
+				title: "Full sidebar demo",
+				status: "completed",
 			},
+			{ messages: [], queued_messages: [] },
 			{ diffUrl: "https://github.com/coder/coder/pull/456" },
 		),
 		webSocket: {
@@ -945,15 +936,12 @@ export const SidebarWithSingleRepo: Story = {
 	parameters: {
 		queries: buildQueries(
 			{
-				chat: {
-					id: CHAT_ID,
-					...baseChatFields,
-					title: "Single repo sidebar",
-					status: "completed",
-				},
-				messages: [],
-				queued_messages: [],
+				id: CHAT_ID,
+				...baseChatFields,
+				title: "Single repo sidebar",
+				status: "completed",
 			},
+			{ messages: [], queued_messages: [] },
 			{ diffUrl: undefined },
 		),
 		webSocket: {
@@ -1010,15 +998,12 @@ export const StreamedReasoningCollapsed: Story = {
 	parameters: {
 		queries: buildQueries(
 			{
-				chat: {
-					id: CHAT_ID,
-					...baseChatFields,
-					title: "Streaming reasoning title",
-					status: "running",
-				},
-				messages: [],
-				queued_messages: [],
+				id: CHAT_ID,
+				...baseChatFields,
+				title: "Streaming reasoning title",
+				status: "running",
 			},
+			{ messages: [], queued_messages: [] },
 			{ diffUrl: undefined },
 		),
 		webSocket: {

site/src/pages/AgentsPage/AgentDetail.tsx

@@ -2,6 +2,7 @@ import { API, watchWorkspace } from "api/api";
 import {
 	chat,
 	chatDiffStatus,
+	chatMessages,
 	chatModelConfigs,
 	chatModels,
 	chats,
@@ -603,8 +604,12 @@ const AgentDetail: FC = () => {
 		...chat(agentId ?? ""),
 		enabled: Boolean(agentId),
 	});
+	const chatMessagesQuery = useQuery({
+		...chatMessages(agentId ?? ""),
+		enabled: Boolean(agentId),
+	});
 	const chatsQuery = useQuery(chats());
-	const workspaceId = chatQuery.data?.chat?.workspace_id;
+	const workspaceId = chatQuery.data?.workspace_id;
 	const workspaceQuery = useQuery({
 		...workspaceById(workspaceId ?? ""),
 		enabled: Boolean(workspaceId),
@@ -669,11 +674,11 @@ const AgentDetail: FC = () => {
 		[proxy.preferredWildcardHostname, workspaceAgent, workspace],
 	);
 
-	const chatData = chatQuery.data;
-	const chatRecord = chatData?.chat;
+	const chatRecord = chatQuery.data;
+	const chatMessagesData = chatMessagesQuery.data;
 	const isArchived = chatRecord?.archived ?? false;
-	const chatMessages = chatData?.messages;
-	const chatQueuedMessages = chatData?.queued_messages;
+	const chatMessagesList = chatMessagesData?.messages;
+	const chatQueuedMessages = chatMessagesData?.queued_messages;
 	const chatLastModelConfigID = chatRecord?.last_model_config_id;
 
 	const modelOptions = useMemo(
@@ -729,9 +734,9 @@ const AgentDetail: FC = () => {
 
 	const { store, clearStreamError } = useChatStore({
 		chatID: agentId,
-		chatMessages,
+		chatMessages: chatMessagesList,
 		chatRecord,
-		chatData,
+		chatMessagesData,
 		chatQueuedMessages,
 		setChatErrorReason,
 		clearChatErrorReason,
@@ -980,7 +985,7 @@ const AgentDetail: FC = () => {
 		inputValueRef,
 	});
 
-	const chatTitle = chatQuery.data?.chat?.title;
+	const chatTitle = chatQuery.data?.title;
 
 	const titleElement = (
 		<title>
@@ -988,7 +993,7 @@ const AgentDetail: FC = () => {
 		</title>
 	);
 
-	const parentChatID = getParentChatID(chatQuery.data?.chat);
+	const parentChatID = getParentChatID(chatQuery.data);
 	const parentChat = parentChatID
 		? chatsQuery.data?.find((chat) => chat.id === parentChatID)
 		: undefined;
@@ -1074,7 +1079,7 @@ const AgentDetail: FC = () => {
 		requestUnarchiveAgent(agentId);
 	};
 
-	if (chatQuery.isLoading) {
+	if (chatQuery.isLoading || chatMessagesQuery.isLoading) {
 		return (
 			<AgentDetailLoadingView
 				titleElement={titleElement}
@@ -1093,7 +1098,7 @@ const AgentDetail: FC = () => {
 		);
 	}
 
-	if (!chatQuery.data || !agentId) {
+	if (!chatQuery.data || !chatMessagesQuery.data || !agentId) {
 		return (
 			<AgentDetailNotFoundView
 				titleElement={titleElement}

site/src/pages/AgentsPage/AgentDetail/ChatContext.test.tsx

@@ -1,6 +1,6 @@
 import { act, render, renderHook, waitFor } from "@testing-library/react";
 import { watchChat } from "api/api";
-import { chatKey, chatsKey } from "api/queries/chats";
+import { chatMessagesKey, chatsKey } from "api/queries/chats";
 
 // The infinite query key used by useInfiniteQuery(infiniteChats())
 // is [...chatsKey, undefined] = ["chats", undefined].
@@ -250,8 +250,7 @@ describe("useChatStore", () => {
 					chatID,
 					chatMessages: [existingMessage],
 					chatRecord: makeChat(chatID),
-					chatData: {
-						chat: makeChat(chatID),
+					chatMessagesData: {
 						messages: [existingMessage],
 						queued_messages: [],
 					},
@@ -331,8 +330,7 @@ describe("useChatStore", () => {
 					chatID,
 					chatMessages: [existingMessage],
 					chatRecord: makeChat(chatID),
-					chatData: {
-						chat: makeChat(chatID),
+					chatMessagesData: {
 						messages: [existingMessage],
 						queued_messages: [],
 					},
@@ -406,8 +404,7 @@ describe("useChatStore", () => {
 					chatID,
 					chatMessages: [existingMessage],
 					chatRecord: makeChat(chatID),
-					chatData: {
-						chat: makeChat(chatID),
+					chatMessagesData: {
 						messages: [existingMessage],
 						queued_messages: [],
 					},
@@ -500,8 +497,7 @@ describe("useChatStore", () => {
 				chatID,
 				chatMessages: [existingMessage],
 				chatRecord: makeChat(chatID),
-				chatData: {
-					chat: makeChat(chatID),
+				chatMessagesData: {
 					messages: [existingMessage],
 					queued_messages: [],
 				},
@@ -574,8 +570,7 @@ describe("useChatStore", () => {
 					chatID,
 					chatMessages: [existingMessage],
 					chatRecord: makeChat(chatID),
-					chatData: {
-						chat: makeChat(chatID),
+					chatMessagesData: {
 						messages: [existingMessage],
 						queued_messages: [],
 					},
@@ -649,8 +644,7 @@ describe("useChatStore", () => {
 					chatID,
 					chatMessages: [existingMessage],
 					chatRecord: makeChat(chatID),
-					chatData: {
-						chat: makeChat(chatID),
+					chatMessagesData: {
 						messages: [existingMessage],
 						queued_messages: [],
 					},
@@ -737,8 +731,7 @@ describe("useChatStore", () => {
 			chatID,
 			chatMessages: [existingMessage],
 			chatRecord: makeChat(chatID),
-			chatData: {
-				chat: makeChat(chatID),
+			chatMessagesData: {
 				messages: [existingMessage],
 				queued_messages: [queuedMessage],
 			},
@@ -781,11 +774,7 @@ describe("useChatStore", () => {
 
 		rerender({
 			...initialOptions,
-			chatData: {
-				chat: {
-					...makeChat(chatID),
-					updated_at: "2025-01-01T00:00:01.000Z",
-				},
+			chatMessagesData: {
 				messages: [existingMessage],
 				queued_messages: [queuedMessage],
 			},
@@ -818,8 +807,7 @@ describe("useChatStore", () => {
 			chatID,
 			chatMessages: [existingMessage],
 			chatRecord: makeChat(chatID),
-			chatData: {
-				chat: makeChat(chatID),
+			chatMessagesData: {
 				messages: [existingMessage],
 				queued_messages: [queuedMessage],
 			},
@@ -853,11 +841,7 @@ describe("useChatStore", () => {
 		// data with an empty queue (no queue_update from WS yet).
 		rerender({
 			...staleOptions,
-			chatData: {
-				chat: {
-					...makeChat(chatID),
-					updated_at: "2025-01-01T00:00:02.000Z",
-				},
+			chatMessagesData: {
 				messages: [existingMessage],
 				queued_messages: [],
 			},
@@ -888,12 +872,11 @@ describe("useChatStore", () => {
 				},
 			},
 		});
-		const initialChatData: TypesGen.ChatWithMessages = {
-			chat: makeChat(chatID),
+		const initialChatMessagesData: TypesGen.ChatMessagesResponse = {
 			messages: [existingMessage],
 			queued_messages: [queuedMessage],
 		};
-		queryClient.setQueryData(chatKey(chatID), initialChatData);
+		queryClient.setQueryData(chatMessagesKey(chatID), initialChatMessagesData);
 
 		const wrapper = ({ children }: PropsWithChildren) => (
 			<QueryClientProvider client={queryClient}>{children}</QueryClientProvider>
@@ -907,7 +890,7 @@ describe("useChatStore", () => {
 					chatID,
 					chatMessages: [existingMessage],
 					chatRecord: makeChat(chatID),
-					chatData: initialChatData,
+					chatMessagesData: initialChatMessagesData,
 					chatQueuedMessages: [queuedMessage],
 					setChatErrorReason,
 					clearChatErrorReason,
@@ -935,8 +918,8 @@ describe("useChatStore", () => {
 			expect(result.current.queuedMessages).toEqual([]);
 		});
 		expect(
-			queryClient.getQueryData<TypesGen.ChatWithMessages | undefined>(
-				chatKey(chatID),
+			queryClient.getQueryData<TypesGen.ChatMessagesResponse | undefined>(
+				chatMessagesKey(chatID),
 			)?.queued_messages,
 		).toEqual([]);
 	});
@@ -970,8 +953,7 @@ describe("useChatStore", () => {
 			chatID: chatID1,
 			chatMessages: [msg1] as TypesGen.ChatMessage[],
 			chatRecord: makeChat(chatID1),
-			chatData: {
-				chat: makeChat(chatID1),
+			chatMessagesData: {
 				messages: [msg1],
 				queued_messages: [] as TypesGen.ChatQueuedMessage[],
 			},
@@ -1019,8 +1001,7 @@ describe("useChatStore", () => {
 			chatID: chatID2,
 			chatMessages: [msg2],
 			chatRecord: makeChat(chatID2),
-			chatData: {
-				chat: makeChat(chatID2),
+			chatMessagesData: {
 				messages: [msg2],
 				queued_messages: [],
 			},
@@ -1057,8 +1038,7 @@ describe("useChatStore", () => {
 					chatID,
 					chatMessages: [existingMessage],
 					chatRecord: makeChat(chatID),
-					chatData: {
-						chat: makeChat(chatID),
+					chatMessagesData: {
 						messages: [existingMessage],
 						queued_messages: [queuedMessage],
 					},
@@ -1113,8 +1093,7 @@ describe("useChatStore", () => {
 					chatID,
 					chatMessages: [existingMessage],
 					chatRecord: makeChat(chatID),
-					chatData: {
-						chat: makeChat(chatID),
+					chatMessagesData: {
 						messages: [existingMessage],
 						queued_messages: [],
 					},
@@ -1215,8 +1194,7 @@ describe("useChatStore", () => {
 					chatID,
 					chatMessages: [existingMessage],
 					chatRecord: makeChat(chatID),
-					chatData: {
-						chat: makeChat(chatID),
+					chatMessagesData: {
 						messages: [existingMessage],
 						queued_messages: [],
 					},
@@ -1311,8 +1289,7 @@ describe("useChatStore", () => {
 			chatID: chatID1,
 			chatMessages: [msg1] as TypesGen.ChatMessage[],
 			chatRecord: makeChat(chatID1),
-			chatData: {
-				chat: makeChat(chatID1),
+			chatMessagesData: {
 				messages: [msg1],
 				queued_messages: [] as TypesGen.ChatQueuedMessage[],
 			},
@@ -1360,8 +1337,7 @@ describe("useChatStore", () => {
 			chatID: chatID2,
 			chatMessages: [msg2],
 			chatRecord: makeChat(chatID2),
-			chatData: {
-				chat: makeChat(chatID2),
+			chatMessagesData: {
 				messages: [msg2],
 				queued_messages: [],
 			},
@@ -1402,8 +1378,7 @@ describe("useChatStore", () => {
 			chatID: chatID1,
 			chatMessages: [msg1] as TypesGen.ChatMessage[],
 			chatRecord: makeChat(chatID1),
-			chatData: {
-				chat: makeChat(chatID1),
+			chatMessagesData: {
 				messages: [msg1],
 				queued_messages: [queuedMsg],
 			},
@@ -1438,8 +1413,7 @@ describe("useChatStore", () => {
 			chatID: chatID2,
 			chatMessages: [],
 			chatRecord: makeChat(chatID2),
-			chatData: {
-				chat: makeChat(chatID2),
+			chatMessagesData: {
 				messages: [],
 				queued_messages: [],
 			},
@@ -1474,8 +1448,7 @@ describe("useChatStore", () => {
 					chatID,
 					chatMessages: [],
 					chatRecord: makeChat(chatID),
-					chatData: {
-						chat: makeChat(chatID),
+					chatMessagesData: {
 						messages: [],
 						queued_messages: [],
 					},
@@ -1544,8 +1517,7 @@ describe("useChatStore", () => {
 					chatID,
 					chatMessages: [],
 					chatRecord: makeChat(chatID),
-					chatData: {
-						chat: makeChat(chatID),
+					chatMessagesData: {
 						messages: [],
 						queued_messages: [],
 					},
@@ -1605,8 +1577,7 @@ describe("useChatStore", () => {
 					chatID,
 					chatMessages: [],
 					chatRecord: makeChat(chatID),
-					chatData: {
-						chat: makeChat(chatID),
+					chatMessagesData: {
 						messages: [],
 						queued_messages: [],
 					},
@@ -1658,8 +1629,7 @@ describe("useChatStore", () => {
 					chatID,
 					chatMessages: [],
 					chatRecord: makeChat(chatID),
-					chatData: {
-						chat: makeChat(chatID),
+					chatMessagesData: {
 						messages: [],
 						queued_messages: [],
 					},
@@ -1719,8 +1689,7 @@ describe("useChatStore", () => {
 					chatID,
 					chatMessages: [],
 					chatRecord: makeChat(chatID),
-					chatData: {
-						chat: makeChat(chatID),
+					chatMessagesData: {
 						messages: [],
 						queued_messages: [],
 					},
@@ -1794,8 +1763,7 @@ describe("useChatStore", () => {
 					chatID,
 					chatMessages: [],
 					chatRecord: makeChat(chatID),
-					chatData: {
-						chat: makeChat(chatID),
+					chatMessagesData: {
 						messages: [],
 						queued_messages: [],
 					},
@@ -1856,8 +1824,7 @@ describe("useChatStore", () => {
 					chatID,
 					chatMessages: [],
 					chatRecord: makeChat(chatID),
-					chatData: {
-						chat: makeChat(chatID),
+					chatMessagesData: {
 						messages: [],
 						queued_messages: [],
 					},
@@ -1928,8 +1895,7 @@ describe("useChatStore", () => {
 					chatID,
 					chatMessages: [],
 					chatRecord: makeChat(chatID),
-					chatData: {
-						chat: makeChat(chatID),
+					chatMessagesData: {
 						messages: [],
 						queued_messages: [],
 					},
@@ -1994,8 +1960,7 @@ describe("useChatStore", () => {
 					chatID,
 					chatMessages: [],
 					chatRecord: makeChat(chatID),
-					chatData: {
-						chat: makeChat(chatID),
+					chatMessagesData: {
 						messages: [],
 						queued_messages: [],
 					},
@@ -2047,8 +2012,7 @@ describe("useChatStore", () => {
 					chatID,
 					chatMessages: [msg],
 					chatRecord: makeChat(chatID),
-					chatData: {
-						chat: makeChat(chatID),
+					chatMessagesData: {
 						messages: [msg],
 						queued_messages: [],
 					},
@@ -2112,8 +2076,7 @@ describe("useChatStore", () => {
 					chatID,
 					chatMessages: [existingMessage],
 					chatRecord: makeChat(chatID),
-					chatData: {
-						chat: makeChat(chatID),
+					chatMessagesData: {
 						messages: [existingMessage],
 						queued_messages: [],
 					},
@@ -2236,8 +2199,7 @@ describe("useChatStore", () => {
 					chatID,
 					chatMessages: [],
 					chatRecord: makeChat(chatID),
-					chatData: {
-						chat: makeChat(chatID),
+					chatMessagesData: {
 						messages: [],
 						queued_messages: [],
 					},
@@ -2305,8 +2267,7 @@ describe("updateSidebarChat via stream events", () => {
 					chatID,
 					chatMessages: [],
 					chatRecord: initialChat,
-					chatData: {
-						chat: initialChat,
+					chatMessagesData: {
 						messages: [],
 						queued_messages: [],
 					},
@@ -2369,8 +2330,7 @@ describe("updateSidebarChat via stream events", () => {
 					chatID,
 					chatMessages: [],
 					chatRecord: initialChat,
-					chatData: {
-						chat: initialChat,
+					chatMessagesData: {
 						messages: [],
 						queued_messages: [],
 					},
@@ -2442,8 +2402,7 @@ describe("updateSidebarChat via stream events", () => {
 					chatID,
 					chatMessages: [],
 					chatRecord: initialChat,
-					chatData: {
-						chat: initialChat,
+					chatMessagesData: {
 						messages: [],
 						queued_messages: [],
 					},
@@ -2508,8 +2467,7 @@ describe("updateSidebarChat via stream events", () => {
 					chatID,
 					chatMessages: [],
 					chatRecord: activeChat,
-					chatData: {
-						chat: activeChat,
+					chatMessagesData: {
 						messages: [],
 						queued_messages: [],
 					},
@@ -2581,8 +2539,7 @@ describe("updateSidebarChat via stream events", () => {
 					chatID,
 					chatMessages: [],
 					chatRecord: initialChat,
-					chatData: {
-						chat: initialChat,
+					chatMessagesData: {
 						messages: [],
 						queued_messages: [],
 					},
@@ -2652,8 +2609,7 @@ describe("updateSidebarChat via stream events", () => {
 					chatID,
 					chatMessages: [],
 					chatRecord: initialChat,
-					chatData: {
-						chat: initialChat,
+					chatMessagesData: {
 						messages: [],
 						queued_messages: [],
 					},
@@ -2718,8 +2674,7 @@ describe("updateSidebarChat via stream events", () => {
 					chatID,
 					chatMessages: [],
 					chatRecord: initialChat,
-					chatData: {
-						chat: initialChat,
+					chatMessagesData: {
 						messages: [],
 						queued_messages: [],
 					},

site/src/pages/AgentsPage/AgentDetail/ChatContext.ts

@@ -1,5 +1,5 @@
 import { watchChat } from "api/api";
-import { chatKey, updateInfiniteChatsCache } from "api/queries/chats";
+import { chatMessagesKey, updateInfiniteChatsCache } from "api/queries/chats";
 import type * as TypesGen from "api/typesGenerated";
 import { asRecord, asString } from "components/ai-elements/runtimeTypeUtils";
 import {
@@ -417,7 +417,7 @@ interface UseChatStoreOptions {
 	chatID: string | undefined;
 	chatMessages: readonly TypesGen.ChatMessage[] | undefined;
 	chatRecord: TypesGen.Chat | undefined;
-	chatData: TypesGen.ChatWithMessages | undefined;
+	chatMessagesData: TypesGen.ChatMessagesResponse | undefined;
 	chatQueuedMessages: readonly TypesGen.ChatQueuedMessage[] | undefined;
 	setChatErrorReason: (chatID: string, reason: string) => void;
 	clearChatErrorReason: (chatID: string) => void;
@@ -444,7 +444,7 @@ export const useChatStore = (
 		chatID,
 		chatMessages,
 		chatRecord,
-		chatData,
+		chatMessagesData,
 		chatQueuedMessages,
 		setChatErrorReason,
 		clearChatErrorReason,
@@ -519,22 +519,22 @@ export const useChatStore = (
 				return;
 			}
 			const nextQueuedMessages = queuedMessages ?? [];
-			queryClient.setQueryData<TypesGen.ChatWithMessages | undefined>(
-				chatKey(chatID),
-				(currentChat) => {
-					if (!currentChat) {
-						return currentChat;
+			queryClient.setQueryData<TypesGen.ChatMessagesResponse | undefined>(
+				chatMessagesKey(chatID),
+				(currentData) => {
+					if (!currentData) {
+						return currentData;
 					}
 					if (
 						chatQueuedMessagesEqualByID(
-							currentChat.queued_messages,
+							currentData.queued_messages,
 							nextQueuedMessages,
 						)
 					) {
-						return currentChat;
+						return currentData;
 					}
 					return {
-						...currentChat,
+						...currentData,
 						queued_messages: nextQueuedMessages,
 					};
 				},
@@ -568,7 +568,7 @@ export const useChatStore = (
 	}, [chatID, store]);
 
 	useEffect(() => {
-		if (!chatID || !chatData) {
+		if (!chatID || !chatMessagesData) {
 			return;
 		}
 		// Allow re-hydration from REST as long as the WebSocket hasn't
@@ -584,7 +584,7 @@ export const useChatStore = (
 		}
 		queuedMessagesHydratedChatIDRef.current = chatID;
 		store.setQueuedMessages(chatQueuedMessages);
-	}, [chatData, chatID, chatQueuedMessages, store]);
+	}, [chatMessagesData, chatID, chatQueuedMessages, store]);
 
 	useEffect(() => {
 		cancelScheduledStreamReset();

site/src/pages/AgentsPage/AgentsPage.tsx

@@ -426,7 +426,7 @@ const AgentsPage: FC = () => {
 						}
 						return chats;
 					});
-					queryClient.setQueryData<TypesGen.ChatWithMessages | undefined>(
+					queryClient.setQueryData<TypesGen.Chat | undefined>(
 						chatKey(updatedChat.id),
 						(previousChat) => {
 							if (!previousChat) {
@@ -434,15 +434,12 @@ const AgentsPage: FC = () => {
 							}
 							return {
 								...previousChat,
-								chat: {
-									...previousChat.chat,
-									...(isStatusEvent && { status: updatedChat.status }),
-									...(isTitleEvent && { title: updatedChat.title }),
-									updated_at:
-										previousChat.chat.updated_at > updatedChat.updated_at
-											? previousChat.chat.updated_at
-											: updatedChat.updated_at,
-								},
+								...(isStatusEvent && { status: updatedChat.status }),
+								...(isTitleEvent && { title: updatedChat.title }),
+								updated_at:
+									previousChat.updated_at > updatedChat.updated_at
+										? previousChat.updated_at
+										: updatedChat.updated_at,
 							};
 						},
 					);