diff --git a/src/components/ChatPane.tsx b/src/components/ChatPane.tsx
index 499a30d..ce4f202 100644
--- a/src/components/ChatPane.tsx
+++ b/src/components/ChatPane.tsx
@@ -244,13 +244,22 @@ export function ChatPane({ session, cfg, messages, onSend, onStop, browsePath, b
           <div class="message-empty">/s/{sid}/chat</div>
         )}
 
-        {messages.map((msg, i) => (
+        {messages.map((msg, i) => {
+          // tool results rendered inline with their preceding call
+          if (msg.role === 'tool' && i > 0 && messages[i-1]?.role === 'call' && messages[i-1]?.name === msg.name) return null
+          return (
           <div key={i} class={`message ${msg.role}`}>
             <div class="msg-bubble">
               {msg.role === 'user' ? (
                 <div class="md" dangerouslySetInnerHTML={{ __html: linkifyPaths((marked.parse(msg.content) as string).replace(/^<p>/, '<p><span class="msg-prefix">u: </span>'), session.cwd) }} />
+              ) : msg.role === 'call' ? (
+                <ToolCall name={msg.name ?? ''} args={msg.content} output={messages[i+1]?.role === 'tool' && messages[i+1]?.name === msg.name ? messages[i+1].content : ''} />
               ) : msg.role === 'tool' ? (
-                <ToolCall content={msg.content} />
+                <ToolOutput text={msg.content} />
+              ) : msg.role === 'reasoning' ? (
+                <details class="reasoning"><summary>thinking</summary><pre>{msg.content}</pre></details>
+              ) : msg.role === 'error' ? (
+                <div class="msg-error">{msg.content}</div>
               ) : msg.role === 'info' ? (
                 <InfoMessage content={msg.content} />
               ) : (
@@ -261,7 +270,8 @@ export function ChatPane({ session, cfg, messages, onSend, onStop, browsePath, b
               )}
             </div>
           </div>
-        ))}
+          )
+        })}
 
         {isRunning && (
           <div class="typing">
@@ -361,15 +371,7 @@ function DiagramModal({ html, onClose }: { html: string; onClose: () => void })
   )
 }
 
-function formatToolContent(raw: string): { name: string; detail: string; body: string; output: string } {
-  // Call is always on the first line; output follows after the newline.
-  const nl = raw.indexOf("\n")
-  const callLine = nl === -1 ? raw : raw.slice(0, nl)
-  const output = nl === -1 ? "" : raw.slice(nl + 1).trimEnd()
-  const m = callLine.match(/^(\w+)\((.*)\)$/)
-  if (!m) return { name: "", detail: "", body: raw, output: "" }
-  const name = m[1]
-  const argsRaw = m[2]
+function formatToolArgs(name: string, argsRaw: string): { detail: string; body: string } {
   try {
     const obj = JSON.parse(argsRaw)
     let detail = ""
@@ -381,9 +383,9 @@ function formatToolContent(raw: string): { name: string; detail: string; body: s
     } else {
       detail = obj.steps?.[0]?.language ?? "bash"
     }
-    return { name, detail, body: JSON.stringify(obj, null, 2), output }
+    return { detail, body: JSON.stringify(obj, null, 2) }
   } catch {
-    return { name, detail: "", body: argsRaw, output }
+    return { detail: "", body: argsRaw }
   }
 }
 
@@ -429,25 +431,34 @@ function InfoMessage({ content }: { content: string }) {
         <span class="tool-name">shell</span>
         <span class="tool-detail">{cmd}</span>
       </div>
-      <pre class="tool-output">{output || '(no output)'}</pre>
+      <ToolOutput text={output || '(no output)'} />
     </div>
   )
 }
 
-function ToolCall({ content }: { content: string }) {
-  const { name, detail, body, output } = formatToolContent(content)
+function ToolOutput({ text }: { text: string }) {
+  const parts = text.split(/\n*^<system-user-interruption>$\n?|\n?^<\/system-user-interruption>$\n*/m)
+  return (
+    <pre class="tool-output">
+      {parts.map((p, i) => i % 2 === 1 ? <span class="user-interruption">{p}</span> : p)}
+    </pre>
+  )
+}
+
+function ToolCall({ name, args, output }: { name: string; args: string; output: string }) {
+  const { detail, body } = formatToolArgs(name, args)
   const [open, setOpen] = useState(false)
   return (
     <div class="tool-call">
       <details open={open} onToggle={(e: Event) => setOpen((e.target as HTMLDetailsElement).open)}>
         <summary class="tool-header">
-          <span class="tool-arrow">{toolIcon(detail)}</span>
-          {name && <span class="tool-name">{name}</span>}
+          <span class="tool-arrow">{toolIcon(detail || name)}</span>
+          <span class="tool-name">{name}</span>
           {detail && <span class="tool-detail">{detail}</span>}
         </summary>
         <pre class="tool-body">{body}</pre>
       </details>
-      {output && <pre class="tool-output">{output}</pre>}
+      {output && <ToolOutput text={output} />}
     </div>
   )
 }
diff --git a/src/lib/chat.ts b/src/lib/chat.ts
index 5f08377..a624faf 100644
--- a/src/lib/chat.ts
+++ b/src/lib/chat.ts
@@ -1,30 +1,27 @@
+export type ChatRole = 'user' | 'assistant' | 'reasoning' | 'call' | 'tool' | 'error' | 'info' | 'retry' | 'exec' | 'stalled' | 'maxsteps'
+
 export interface ChatMessage {
-  role: 'user' | 'assistant' | 'tool' | 'info'
+  role: ChatRole
+  name?: string
   content: string
 }
 
-// Parse the ollie chat log format (lines returned by the gateway).
-// Lines starting with "user: " or "assistant: " begin a new message;
-// subsequent lines are appended to the current message content.
+const headerRe = /^\[(\w+)(?::([^\]]+))?\]$/
+
+// Parse the ollie chat log format. Each block starts with a [role] or
+// [role:name] header line; content runs until the next header.
 export function parseChat(lines: string[]): ChatMessage[] {
   const messages: ChatMessage[] = []
   let cur: ChatMessage | null = null
 
   for (const line of lines) {
-    if (line.startsWith('user: ')) {
+    const m = headerRe.exec(line)
+    if (m) {
       if (cur) messages.push(cur)
-      cur = { role: 'user', content: line.slice(6) }
-    } else if (line.startsWith('assistant: ')) {
-      if (cur) messages.push(cur)
-      cur = { role: 'assistant', content: line.slice(11) }
-    } else if (line.startsWith('-> ')) {
-      if (cur) messages.push(cur)
-      cur = { role: 'tool', content: line.slice(3) }
-    } else if (line.startsWith(':: ')) {
-      if (cur) messages.push(cur)
-      cur = { role: 'info', content: line.slice(3) }
+      cur = { role: m[1] as ChatRole, content: '' }
+      if (m[2]) cur.name = m[2]
     } else if (cur) {
-      cur.content += '\n' + line
+      cur.content += (cur.content ? '\n' : '') + line
     }
   }
   if (cur) messages.push(cur)
diff --git a/src/style.css b/src/style.css
index 361819d..e7520b3 100644
--- a/src/style.css
+++ b/src/style.css
@@ -552,6 +552,16 @@ input, select, textarea { font-family: inherit; }
 .md th { background: var(--bg-soft); font-weight: 600; }
 
 /* ---- Tool calls ---- */
+.message.call { justify-content: flex-start; }
+.message.call .msg-bubble {
+  max-width: 100%;
+  width: 100%;
+  background: var(--tool-bubble-bg);
+  border: 1px solid var(--border);
+  border-radius: var(--r-md);
+  padding: 0;
+  overflow: hidden;
+}
 .message.tool { justify-content: flex-start; }
 .message.tool .msg-bubble {
   max-width: 100%;
@@ -812,6 +822,22 @@ details[open] > .tool-header::before {
   padding: 0;
   margin: 4px 0;
 }
+[data-theme="acme"] .message.call .msg-bubble {
+  border-radius: var(--r-sm);
+  margin: 4px 0;
+}
+[data-theme="acme"] .message.reasoning .msg-bubble {
+  padding: 0;
+}
+[data-theme="acme"] .message.error .msg-bubble {
+  border-radius: var(--r-sm);
+  margin: 4px 0;
+}
+[data-theme="acme"] .user-interruption {
+  background: rgba(147, 112, 219, 0.12);
+  border-color: rgba(147, 112, 219, 0.4);
+  color: #6b21a8;
+}
 [data-theme="acme"] .shell-block {
   background: #fff;
   border: 1px solid var(--border);
@@ -1072,6 +1098,54 @@ details[open] > .tool-header::before {
   overflow-x: auto;
 }
 
+/* ---- Reasoning ---- */
+.message.reasoning { justify-content: flex-start; }
+.message.reasoning .msg-bubble {
+  background: transparent;
+  border: none;
+  padding: 2px 8px;
+}
+.reasoning summary {
+  font-family: var(--mono);
+  font-size: 12px;
+  color: var(--text-faint);
+  cursor: pointer;
+}
+.reasoning pre {
+  font-family: var(--mono);
+  font-size: 12px;
+  line-height: 1.5;
+  color: var(--text-dim);
+  white-space: pre-wrap;
+  margin: 4px 0 0;
+}
+
+/* ---- Error messages ---- */
+.message.error { justify-content: flex-start; }
+.message.error .msg-bubble {
+  background: rgba(251, 113, 133, 0.06);
+  border: 1px solid rgba(251, 113, 133, 0.25);
+  border-radius: var(--r-md);
+}
+.msg-error {
+  font-family: var(--mono);
+  font-size: 12px;
+  color: var(--danger);
+}
+
+/* ---- User interruption ---- */
+.user-interruption {
+  display: block;
+  margin: 6px 0 2px;
+  padding: 6px 10px;
+  background: rgba(139, 92, 246, 0.08);
+  border: 1px solid rgba(139, 92, 246, 0.3);
+  border-radius: var(--r-sm);
+  color: #b49aef;
+  font-style: normal;
+  white-space: pre-wrap;
+}
+
 /* ---- Info messages ---- */
 .message.info { justify-content: flex-start; }
 .message.info .msg-bubble {