diff --git a/internal/api/handlers_chat.go b/internal/api/handlers_chat.go
index ddbba05..6378c6a 100644
--- a/internal/api/handlers_chat.go
+++ b/internal/api/handlers_chat.go
@@ -4,12 +4,15 @@ import (
 	"context"
 	"encoding/json"
 	"net/http"
+	"regexp"
 	"strings"
 
 	"github.com/muyue/muyue/internal/agent"
 	"github.com/muyue/muyue/internal/orchestrator"
 )
 
+var thinkingTagRegex = regexp.MustCompile(`(?s)<[Tt]hink[^>]*>.*?</[Tt]hink>`)
+
 const maxToolIterations = 15
 
 func (s *Server) handleChat(w http.ResponseWriter, r *http.Request) {
@@ -68,12 +71,11 @@ func (s *Server) handleStreamChat(w http.ResponseWriter, orb *orchestrator.Orche
 	}
 
 	ctx := context.Background()
-	messages := []orchestrator.Message{
-		{Role: "user", Content: userMessage},
-	}
+	messages := s.buildContextMessages(userMessage)
 
 	var finalContent string
 	var allToolCalls []map[string]interface{}
+	var allToolResults []map[string]interface{}
 
 	for i := 0; i < maxToolIterations; i++ {
 		resp, err := orb.SendWithTools(messages)
@@ -86,8 +88,13 @@ func (s *Server) handleStreamChat(w http.ResponseWriter, orb *orchestrator.Orche
 		content := cleanThinkingTags(choice.Message.Content)
 
 		if content != "" {
-			for _, ch := range strings.Split(content, "") {
-				writeSSE(map[string]interface{}{"content": ch})
+			words := strings.Fields(content)
+			for i, w := range words {
+				chunk := w
+				if i < len(words)-1 {
+					chunk += " "
+				}
+				writeSSE(map[string]interface{}{"content": chunk})
 			}
 			finalContent = content
 		}
@@ -133,6 +140,14 @@ func (s *Server) handleStreamChat(w http.ResponseWriter, orb *orchestrator.Orche
 			}
 			writeSSE(map[string]interface{}{"tool_result": resultData})
 
+			allToolResults = append(allToolResults, map[string]interface{}{
+				"tool_call_id": tc.ID,
+				"name":         tc.Function.Name,
+				"args":         tc.Function.Arguments,
+				"result":       result.Content,
+				"is_error":     result.IsError,
+			})
+
 			messages = append(messages, orchestrator.Message{
 				Role:       "tool",
 				Content:    result.Content,
@@ -146,7 +161,11 @@ func (s *Server) handleStreamChat(w http.ResponseWriter, orb *orchestrator.Orche
 
 	storeContent := finalContent
 	if len(allToolCalls) > 0 {
-		storeObj := map[string]interface{}{"content": storeContent, "tool_calls": allToolCalls}
+		storeObj := map[string]interface{}{
+			"content":      storeContent,
+			"tool_calls":   allToolCalls,
+			"tool_results": allToolResults,
+		}
 		storeJSON, _ := json.Marshal(storeObj)
 		storeContent = string(storeJSON)
 	}
@@ -157,9 +176,7 @@ func (s *Server) handleStreamChat(w http.ResponseWriter, orb *orchestrator.Orche
 
 func (s *Server) handleNonStreamChat(w http.ResponseWriter, orb *orchestrator.Orchestrator, userMessage string) {
 	ctx := context.Background()
-	messages := []orchestrator.Message{
-		{Role: "user", Content: userMessage},
-	}
+	messages := s.buildContextMessages(userMessage)
 
 	var finalContent string
 
@@ -223,7 +240,59 @@ func (s *Server) handleNonStreamChat(w http.ResponseWriter, orb *orchestrator.Or
 }
 
 func cleanThinkingTags(content string) string {
-	return strings.ReplaceAll(content, "<think", "")
+	return strings.TrimSpace(thinkingTagRegex.ReplaceAllString(content, ""))
+}
+
+const contextWindowMessages = 20
+
+func (s *Server) buildContextMessages(userMessage string) []orchestrator.Message {
+	history := s.convStore.Get()
+	start := 0
+	if len(history) > contextWindowMessages {
+		start = len(history) - contextWindowMessages
+	}
+
+	messages := make([]orchestrator.Message, 0, len(history[start:])+1)
+
+	summary := s.convStore.GetSummary()
+	if summary != "" {
+		messages = append(messages, orchestrator.Message{
+			Role:    "system",
+			Content: "Résumé de la conversation précédente:\n" + summary,
+		})
+	}
+
+	for _, m := range history[start:] {
+		content := m.Content
+		if m.Role == "assistant" {
+			var parsed struct {
+				Content   string `json:"content"`
+				ToolCalls []struct {
+					ToolCallID string `json:"tool_call_id"`
+					Name       string `json:"name"`
+					Args       string `json:"args"`
+				} `json:"tool_calls"`
+			}
+			if err := json.Unmarshal([]byte(content), &parsed); err == nil && parsed.Content != "" {
+				content = parsed.Content
+			}
+		}
+		role := m.Role
+		if role == "system" {
+			continue
+		}
+		messages = append(messages, orchestrator.Message{
+			Role:    role,
+			Content: content,
+		})
+	}
+
+	messages = append(messages, orchestrator.Message{
+		Role:    "user",
+		Content: userMessage,
+	})
+
+	return messages
 }
 
 func (s *Server) autoSummarize() {
diff --git a/internal/api/handlers_shell_chat.go b/internal/api/handlers_shell_chat.go
index c33d829..60bb0d3 100644
--- a/internal/api/handlers_shell_chat.go
+++ b/internal/api/handlers_shell_chat.go
@@ -136,8 +136,13 @@ func (s *Server) handleShellChatStream(w http.ResponseWriter, orb *orchestrator.
 		content := cleanThinkingTags(choice.Message.Content)
 
 		if content != "" {
-			for _, ch := range strings.Split(content, "") {
-				writeSSE(map[string]interface{}{"content": ch})
+			words := strings.Fields(content)
+			for i, w := range words {
+				chunk := w
+				if i < len(words)-1 {
+					chunk += " "
+				}
+				writeSSE(map[string]interface{}{"content": chunk})
 			}
 			finalContent = content
 		}
diff --git a/web/src/api/client.js b/web/src/api/client.js
index 91a8cc4..1aa75c5 100644
--- a/web/src/api/client.js
+++ b/web/src/api/client.js
@@ -52,7 +52,7 @@ const api = {
   saveTerminalSettings: (settings) => request('/terminal/settings', { method: 'PUT', body: JSON.stringify(settings) }),
   getChatHistory: () => request('/chat/history'),
   clearChat: () => request('/chat/clear', { method: 'POST' }),
-  sendChat: (message, stream = true, onChunk) => {
+  sendChat: (message, stream = true, onChunk, signal) => {
     if (!stream) {
       return request('/chat', { method: 'POST', body: JSON.stringify({ message, stream: false }) })
     }
@@ -61,6 +61,7 @@ const api = {
         method: 'POST',
         headers: { 'Content-Type': 'application/json' },
         body: JSON.stringify({ message, stream: true }),
+        signal,
       }).then(async (res) => {
         if (!res.ok) {
           const err = await res.json().catch(() => ({ error: res.statusText }))
diff --git a/web/src/components/Studio.jsx b/web/src/components/Studio.jsx
index 8a124a1..21af5e3 100644
--- a/web/src/components/Studio.jsx
+++ b/web/src/components/Studio.jsx
@@ -59,8 +59,9 @@ function formatText(text) {
     .replace(/`([^`]+)`/g, '<code class="inline-code">$1</code>')
     .replace(/^### (.+)$/gm, '<h4 class="msg-h4">$1</h4>')
     .replace(/^## (.+)$/gm, '<h3 class="msg-h3">$1</h3>')
-    .replace(/^\s*[-*] (.+)$/gm, '<span class="msg-bullet">$1</span>')
-    .replace(/^\s*(\d+)[.)] (.+)$/gm, '<span class="msg-step"><span class="msg-step-num">$1</span>$2</span>')
+    .replace(/^# (.+)$/gm, '<h2 class="msg-h2">$1</h2>')
+    .replace(/^\s*[-*] (.+)$/gm, '<div class="msg-bullet">• $1</div>')
+    .replace(/^\s*(\d+)[.)] (.+)$/gm, '<div class="msg-step"><span class="msg-step-num">$1</span> $2</div>')
 }
 
 function ThinkingBlock({ content, done }) {
@@ -151,11 +152,13 @@ function FeedItem({ msg }) {
   const timeStr = msg.time ? new Date(msg.time).toLocaleTimeString([], { hour: '2-digit', minute: '2-digit' }) : ''
 
   let parsedToolCalls = null
+  let parsedToolResults = null
   let displayContent = msg.content
   try {
     const parsed = JSON.parse(msg.content)
     if (parsed && Array.isArray(parsed.tool_calls)) {
       parsedToolCalls = parsed.tool_calls
+      parsedToolResults = parsed.tool_results || null
       displayContent = parsed.content || ''
     }
   } catch {}
@@ -186,9 +189,15 @@ function FeedItem({ msg }) {
           {timeStr && <span className="feed-time">{timeStr}</span>}
         </div>
         {msg.thinking && <ThinkingBlock content={msg.thinking} done />}
-        {parsedToolCalls && parsedToolCalls.map((tc, i) => (
-          <ToolCallBlock key={tc.tool_call_id || i} call={tc} result={null} />
-        ))}
+        {parsedToolCalls && parsedToolCalls.map((tc, i) => {
+          const resultData = parsedToolResults
+            ? parsedToolResults.find(r => r.tool_call_id === tc.tool_call_id)
+            : null
+          const result = resultData
+            ? { content: resultData.result, is_error: resultData.is_error }
+            : null
+          return <ToolCallBlock key={tc.tool_call_id || i} call={tc} result={result} />
+        })}
         {cleanContent && (
           <div className="feed-content">
             {renderContent(cleanContent).map((part, i) =>
@@ -265,6 +274,7 @@ export default function Studio({ api }) {
   const [loaded, setLoaded] = useState(false)
   const messagesEnd = useRef(null)
   const textareaRef = useRef(null)
+  const abortRef = useRef(null)
 
   useEffect(() => {
     api.getChatHistory().then(data => {
@@ -321,6 +331,9 @@ export default function Studio({ api }) {
     setStreamThinking('')
     setStreamToolCalls([])
 
+    const controller = new AbortController()
+    abortRef.current = controller
+
     try {
       let accumulated = ''
       let thinking = ''
@@ -349,7 +362,7 @@ export default function Studio({ api }) {
         }
         accumulated = partial
         setStreaming(partial)
-      })
+      }, controller.signal)
 
       const finalContent = accumulated || t('studio.noResponse')
       const aiMsg = {
@@ -367,19 +380,37 @@ export default function Studio({ api }) {
       }
       setMessages(prev => [...prev, aiMsg])
     } catch (err) {
-      setMessages(prev => [...prev, {
-        id: (Date.now() + 1).toString(),
-        role: 'system',
-        content: `${t('studio.error')}: ${err.message}`,
-        time: new Date().toISOString(),
-      }])
+      if (err.name === 'AbortError') {
+        if (streaming) {
+          setMessages(prev => [...prev, {
+            id: (Date.now() + 1).toString(),
+            role: 'system',
+            content: t('studio.cancelled'),
+            time: new Date().toISOString(),
+          }])
+        }
+      } else {
+        setMessages(prev => [...prev, {
+          id: (Date.now() + 1).toString(),
+          role: 'system',
+          content: `${t('studio.error')}: ${err.message}`,
+          time: new Date().toISOString(),
+        }])
+      }
     } finally {
       setLoading(false)
       setStreaming('')
       setStreamThinking('')
       setStreamToolCalls([])
+      abortRef.current = null
     }
-  }, [input, loading, api, t, handleClear])
+  }, [input, loading, api, t, handleClear, streaming])
+
+  const handleStop = useCallback(() => {
+    if (abortRef.current) {
+      abortRef.current.abort()
+    }
+  }, [])
 
   const handleKeyDown = (e) => {
     if (e.key === 'Enter' && !e.shiftKey) {
@@ -432,6 +463,13 @@ export default function Studio({ api }) {
               <line x1="22" y1="2" x2="11" y2="13"/><polygon points="22 2 15 22 11 13 2 9 22 2"/>
             </svg>
           </button>
+          {loading && (
+            <button className="studio-stop-btn" onClick={handleStop} title={t('studio.stop')}>
+              <svg width="16" height="16" viewBox="0 0 24 24" fill="currentColor">
+                <rect x="4" y="4" width="16" height="16" rx="2"/>
+              </svg>
+            </button>
+          )}
         </div>
         <div className="studio-input-hint">
           {t('studio.inputHint')} &middot; /clear
diff --git a/web/src/i18n/en.js b/web/src/i18n/en.js
index ba56892..0b8b066 100644
--- a/web/src/i18n/en.js
+++ b/web/src/i18n/en.js
@@ -90,6 +90,8 @@ const en = {
     you: 'You',
     mentioned: 'mentioned',
     cleared: 'Conversation cleared.',
+    cancelled: 'Request cancelled.',
+    stop: 'Stop',
   },
 
   shell: {
diff --git a/web/src/i18n/fr.js b/web/src/i18n/fr.js
index 408c5a5..1e8f569 100644
--- a/web/src/i18n/fr.js
+++ b/web/src/i18n/fr.js
@@ -90,6 +90,8 @@ const fr = {
     you: 'Vous',
     mentioned: 'mentionn\u00e9',
     cleared: 'Conversation effac\u00e9e.',
+    cancelled: 'Requ\u00eate annul\u00e9e.',
+    stop: 'Stop',
   },
 
   shell: {
diff --git a/web/src/styles/global.css b/web/src/styles/global.css
index 7e855ac..31dfa28 100644
--- a/web/src/styles/global.css
+++ b/web/src/styles/global.css
@@ -752,6 +752,12 @@ input::placeholder { color: var(--text-disabled); }
 }
 .studio-send-btn:hover:not(:disabled) { background: var(--accent-bright); border-color: var(--accent-bright); }
 .studio-send-btn:disabled { opacity: 0.3; cursor: not-allowed; }
+.studio-stop-btn {
+  width: 42px; height: 42px; padding: 0; display: flex; align-items: center; justify-content: center;
+  border-radius: var(--radius); background: var(--error); color: #fff; border: 1px solid var(--error);
+  cursor: pointer; transition: all 0.15s; flex-shrink: 0;
+}
+.studio-stop-btn:hover { opacity: 0.8; }
 .studio-input-hint { font-size: 11px; color: var(--text-disabled); text-align: center; margin-top: 6px; }
 
 /* ── Studio Tool Blocks ── */