diff --git a/src/main/AryxAppService.ts b/src/main/AryxAppService.ts
index ff7d21d..1d252d1 100644
--- a/src/main/AryxAppService.ts
+++ b/src/main/AryxAppService.ts
@@ -1199,6 +1199,7 @@ export class AryxAppService extends EventEmitter<AppServiceEvents> {
       permissionKind: event.permissionKind,
       title: event.title,
       detail: event.detail,
+      permissionDetail: event.permissionDetail,
     };
   }
 
diff --git a/src/renderer/components/chat/ApprovalBanner.tsx b/src/renderer/components/chat/ApprovalBanner.tsx
index e2fa210..2964456 100644
--- a/src/renderer/components/chat/ApprovalBanner.tsx
+++ b/src/renderer/components/chat/ApprovalBanner.tsx
@@ -2,6 +2,7 @@ import { useState } from 'react';
 import { Bot, Check, ChevronDown, Loader2, ShieldAlert, ShieldCheck, X } from 'lucide-react';
 
 import { MarkdownContent } from '@renderer/components/MarkdownContent';
+import { permissionDetailSummary, PermissionDetailView } from '@renderer/components/chat/PermissionDetailView';
 import type { ApprovalDecision, PendingApprovalRecord } from '@shared/domain/approval';
 
 /* ── ApprovalBanner ────────────────────────────────────────── */
@@ -47,9 +48,11 @@ export function ApprovalBanner({
             {approval.permissionKind && <span>Permission: <span className="text-zinc-300">{approval.permissionKind}</span></span>}
           </div>
 
-          {approval.detail && (
-            <p className="mt-1.5 text-[12px] leading-relaxed text-zinc-400">{approval.detail}</p>
-          )}
+          {approval.permissionDetail
+            ? <PermissionDetailView detail={approval.permissionDetail} />
+            : approval.detail && (
+              <p className="mt-1.5 text-[12px] leading-relaxed text-zinc-400">{approval.detail}</p>
+            )}
         </div>
       </div>
 
@@ -134,7 +137,9 @@ export function QueuedApprovalsList({ approvals }: { approvals: PendingApprovalR
                 key={approval.id}
               >
                 <ShieldAlert className="size-3 shrink-0 text-zinc-600" />
-                <span className="min-w-0 flex-1 truncate text-[11px] text-zinc-400">{approval.title}</span>
+                <span className="min-w-0 flex-1 truncate text-[11px] text-zinc-400">
+                  {(approval.permissionDetail && permissionDetailSummary(approval.permissionDetail)) || approval.title}
+                </span>
                 <span className="shrink-0 rounded-full bg-zinc-800 px-1.5 py-0.5 text-[8px] font-semibold uppercase tracking-wider text-zinc-500">
                   {kindLabel}
                 </span>
diff --git a/src/renderer/components/chat/PermissionDetailView.tsx b/src/renderer/components/chat/PermissionDetailView.tsx
new file mode 100644
index 0000000..8d8aa0b
--- /dev/null
+++ b/src/renderer/components/chat/PermissionDetailView.tsx
@@ -0,0 +1,295 @@
+import { useState } from 'react';
+import {
+  AlertTriangle,
+  BookOpen,
+  ChevronDown,
+  ExternalLink,
+  FileEdit,
+  FileText,
+  Globe,
+  Server,
+  Terminal,
+} from 'lucide-react';
+
+import type { PermissionDetail } from '@shared/contracts/sidecar';
+
+export function PermissionDetailView({ detail }: { detail: PermissionDetail }) {
+  switch (detail.kind) {
+    case 'shell':
+      return <ShellDetail detail={detail} />;
+    case 'write':
+      return <WriteDetail detail={detail} />;
+    case 'read':
+      return <ReadDetail detail={detail} />;
+    case 'mcp':
+      return <McpDetail detail={detail} />;
+    case 'url':
+      return <UrlDetail detail={detail} />;
+    case 'memory':
+      return <MemoryDetail detail={detail} />;
+    case 'custom-tool':
+      return <CustomToolDetail detail={detail} />;
+    case 'hook':
+      return <HookDetail detail={detail} />;
+    default:
+      return null;
+  }
+}
+
+export function permissionDetailSummary(detail: PermissionDetail): string | undefined {
+  switch (detail.kind) {
+    case 'shell':
+      return detail.command ? truncate(detail.command, 80) : undefined;
+    case 'write':
+      return detail.fileName;
+    case 'read':
+      return detail.path;
+    case 'url':
+      return detail.url;
+    case 'mcp':
+      return detail.serverName
+        ? `${detail.serverName} → ${detail.toolTitle ?? ''}`
+        : detail.toolTitle;
+    case 'memory':
+      return detail.subject;
+    case 'custom-tool':
+      return detail.toolDescription ? truncate(detail.toolDescription, 80) : undefined;
+    case 'hook':
+      return detail.hookMessage ? truncate(detail.hookMessage, 80) : undefined;
+    default:
+      return undefined;
+  }
+}
+
+/* ── Kind-specific renderers ────────────────────────────────── */
+
+function ShellDetail({ detail }: { detail: PermissionDetail }) {
+  return (
+    <div className="mt-2.5 space-y-2">
+      {detail.intention && <IntentionLine text={detail.intention} />}
+      {detail.warning && (
+        <div className="flex items-start gap-1.5 rounded-md bg-red-500/10 px-2.5 py-1.5 text-[11px] text-red-300">
+          <AlertTriangle className="mt-0.5 size-3 shrink-0" />
+          <span>{detail.warning}</span>
+        </div>
+      )}
+      {detail.command && <CommandBlock text={detail.command} />}
+      {detail.possiblePaths && detail.possiblePaths.length > 0 && (
+        <MetaList label="Paths" items={detail.possiblePaths} />
+      )}
+      {detail.possibleUrls && detail.possibleUrls.length > 0 && (
+        <MetaList label="URLs" items={detail.possibleUrls} />
+      )}
+    </div>
+  );
+}
+
+function WriteDetail({ detail }: { detail: PermissionDetail }) {
+  return (
+    <div className="mt-2.5 space-y-2">
+      {detail.intention && <IntentionLine text={detail.intention} />}
+      {detail.fileName && (
+        <div className="flex items-center gap-1.5 text-[11px] text-zinc-300">
+          <FileEdit className="size-3 shrink-0 text-zinc-500" />
+          <code className="font-mono">{detail.fileName}</code>
+        </div>
+      )}
+      {detail.diff && <DiffBlock text={detail.diff} />}
+      {!detail.diff && detail.newFileContents && (
+        <CollapsibleCode label="New file contents" text={detail.newFileContents} />
+      )}
+    </div>
+  );
+}
+
+function ReadDetail({ detail }: { detail: PermissionDetail }) {
+  return (
+    <div className="mt-2.5 space-y-2">
+      {detail.intention && <IntentionLine text={detail.intention} />}
+      {detail.path && (
+        <div className="flex items-center gap-1.5 text-[11px] text-zinc-300">
+          <FileText className="size-3 shrink-0 text-zinc-500" />
+          <code className="font-mono">{detail.path}</code>
+        </div>
+      )}
+    </div>
+  );
+}
+
+function McpDetail({ detail }: { detail: PermissionDetail }) {
+  return (
+    <div className="mt-2.5 space-y-2">
+      <div className="flex flex-wrap items-center gap-2 text-[11px]">
+        {detail.serverName && (
+          <span className="inline-flex items-center gap-1 rounded-full bg-indigo-500/15 px-2 py-0.5 text-indigo-300">
+            <Server className="size-2.5" />
+            {detail.serverName}
+          </span>
+        )}
+        {detail.toolTitle && <span className="text-zinc-300">{detail.toolTitle}</span>}
+        {detail.readOnly && (
+          <span className="rounded-full bg-emerald-500/15 px-1.5 py-0.5 text-[9px] font-semibold uppercase tracking-wider text-emerald-400">
+            read-only
+          </span>
+        )}
+      </div>
+      {detail.args && Object.keys(detail.args).length > 0 && (
+        <CollapsibleCode label="Arguments" text={JSON.stringify(detail.args, null, 2)} />
+      )}
+    </div>
+  );
+}
+
+function UrlDetail({ detail }: { detail: PermissionDetail }) {
+  return (
+    <div className="mt-2.5 space-y-2">
+      {detail.intention && <IntentionLine text={detail.intention} />}
+      {detail.url && (
+        <div className="flex items-center gap-1.5 rounded-md bg-zinc-800/60 px-2.5 py-1.5 text-[11px] text-blue-300">
+          <Globe className="size-3 shrink-0" />
+          <code className="min-w-0 flex-1 break-all font-mono">{detail.url}</code>
+          <ExternalLink className="size-3 shrink-0 text-zinc-500" />
+        </div>
+      )}
+    </div>
+  );
+}
+
+function MemoryDetail({ detail }: { detail: PermissionDetail }) {
+  return (
+    <div className="mt-2.5 space-y-1.5">
+      {detail.subject && (
+        <div className="flex items-center gap-1.5 text-[11px]">
+          <BookOpen className="size-3 shrink-0 text-zinc-500" />
+          <span className="font-medium text-zinc-300">{detail.subject}</span>
+        </div>
+      )}
+      {detail.fact && (
+        <p className="rounded-md bg-zinc-800/60 px-2.5 py-1.5 text-[11px] leading-relaxed text-zinc-300">
+          {detail.fact}
+        </p>
+      )}
+      {detail.citations && (
+        <p className="text-[10px] text-zinc-500">
+          Source: <span className="text-zinc-400">{detail.citations}</span>
+        </p>
+      )}
+    </div>
+  );
+}
+
+function CustomToolDetail({ detail }: { detail: PermissionDetail }) {
+  return (
+    <div className="mt-2.5 space-y-2">
+      {detail.toolDescription && (
+        <p className="text-[11px] text-zinc-400">{detail.toolDescription}</p>
+      )}
+      {detail.args && Object.keys(detail.args).length > 0 && (
+        <CollapsibleCode label="Arguments" text={JSON.stringify(detail.args, null, 2)} />
+      )}
+    </div>
+  );
+}
+
+function HookDetail({ detail }: { detail: PermissionDetail }) {
+  return (
+    <div className="mt-2.5 space-y-2">
+      {detail.hookMessage && (
+        <div className="flex items-start gap-1.5 rounded-md bg-amber-500/10 px-2.5 py-1.5 text-[11px] text-amber-200">
+          <AlertTriangle className="mt-0.5 size-3 shrink-0" />
+          <span>{detail.hookMessage}</span>
+        </div>
+      )}
+      {detail.args && Object.keys(detail.args).length > 0 && (
+        <CollapsibleCode label="Arguments" text={JSON.stringify(detail.args, null, 2)} />
+      )}
+    </div>
+  );
+}
+
+/* ── Shared primitives ──────────────────────────────────────── */
+
+function IntentionLine({ text }: { text: string }) {
+  return <p className="text-[11px] italic text-zinc-400">{text}</p>;
+}
+
+function CommandBlock({ text }: { text: string }) {
+  return (
+    <pre className="overflow-x-auto rounded-md bg-zinc-900/80 px-3 py-2 font-mono text-[11px] leading-relaxed text-emerald-300">
+      {text}
+    </pre>
+  );
+}
+
+function DiffBlock({ text }: { text: string }) {
+  const lines = text.split('\n');
+  return (
+    <CollapsibleCode label="Diff" text={text} defaultExpanded>
+      <pre className="max-h-48 overflow-auto rounded-md bg-zinc-900/80 px-3 py-2 font-mono text-[10px] leading-relaxed">
+        {lines.map((line, i) => {
+          let color = 'text-zinc-400';
+          if (line.startsWith('+')) color = 'text-emerald-400';
+          else if (line.startsWith('-')) color = 'text-red-400';
+          else if (line.startsWith('@@')) color = 'text-blue-400';
+          return (
+            <div className={color} key={i}>
+              {line}
+            </div>
+          );
+        })}
+      </pre>
+    </CollapsibleCode>
+  );
+}
+
+function CollapsibleCode({
+  label,
+  text,
+  children,
+  defaultExpanded = false,
+}: {
+  label: string;
+  text: string;
+  children?: React.ReactNode;
+  defaultExpanded?: boolean;
+}) {
+  const [expanded, setExpanded] = useState(defaultExpanded);
+
+  return (
+    <div className="rounded-md border border-zinc-800/60 bg-zinc-900/40">
+      <button
+        aria-expanded={expanded}
+        className="flex w-full items-center gap-1.5 px-2.5 py-1.5 text-left text-[10px] font-medium text-zinc-500 hover:text-zinc-400"
+        onClick={() => setExpanded(!expanded)}
+        type="button"
+      >
+        <ChevronDown
+          className={`size-2.5 transition-transform ${expanded ? 'rotate-180' : ''}`}
+        />
+        {label}
+      </button>
+      {expanded && (
+        <div className="border-t border-zinc-800/40 px-2.5 py-1.5">
+          {children ?? (
+            <pre className="max-h-48 overflow-auto font-mono text-[10px] leading-relaxed text-zinc-300">
+              {text}
+            </pre>
+          )}
+        </div>
+      )}
+    </div>
+  );
+}
+
+function MetaList({ label, items }: { label: string; items: string[] }) {
+  return (
+    <div className="text-[10px] text-zinc-500">
+      <span className="font-medium">{label}:</span>{' '}
+      <span className="text-zinc-400">{items.join(', ')}</span>
+    </div>
+  );
+}
+
+function truncate(text: string, maxLength: number): string {
+  return text.length <= maxLength ? text : `${text.slice(0, maxLength)}…`;
+}
diff --git a/src/shared/contracts/sidecar.ts b/src/shared/contracts/sidecar.ts
index 1354a03..a51b5ff 100644
--- a/src/shared/contracts/sidecar.ts
+++ b/src/shared/contracts/sidecar.ts
@@ -181,6 +181,30 @@ export interface AgentActivityEvent {
   toolName?: string;
 }
 
+export interface PermissionDetail {
+  kind: string;
+  intention?: string;
+  command?: string;
+  warning?: string;
+  possiblePaths?: string[];
+  possibleUrls?: string[];
+  hasWriteFileRedirection?: boolean;
+  fileName?: string;
+  diff?: string;
+  newFileContents?: string;
+  path?: string;
+  serverName?: string;
+  toolTitle?: string;
+  args?: Record<string, unknown>;
+  readOnly?: boolean;
+  url?: string;
+  subject?: string;
+  fact?: string;
+  citations?: string;
+  toolDescription?: string;
+  hookMessage?: string;
+}
+
 export interface ApprovalRequestedEvent {
   type: 'approval-requested';
   requestId: string;
@@ -193,6 +217,7 @@ export interface ApprovalRequestedEvent {
   permissionKind?: string;
   title: string;
   detail?: string;
+  permissionDetail?: PermissionDetail;
 }
 
 export interface CommandErrorEvent {
diff --git a/src/shared/domain/approval.ts b/src/shared/domain/approval.ts
index 84078aa..ea14eef 100644
--- a/src/shared/domain/approval.ts
+++ b/src/shared/domain/approval.ts
@@ -1,3 +1,5 @@
+import type { PermissionDetail } from '@shared/contracts/sidecar';
+
 export type ApprovalCheckpointKind = 'tool-call' | 'final-response';
 export type ApprovalStatus = 'pending' | 'approved' | 'rejected';
 export type ApprovalDecision = Exclude<ApprovalStatus, 'pending'>;
@@ -35,6 +37,7 @@ export interface PendingApprovalRecord {
   title: string;
   detail?: string;
   messages?: PendingApprovalMessageRecord[];
+  permissionDetail?: PermissionDetail;
 }
 
 export interface PendingApprovalState {
@@ -290,6 +293,7 @@ export function normalizePendingApproval(
     title,
     detail: normalizeOptionalString(approval?.detail),
     messages: normalizePendingApprovalMessages(approval?.messages),
+    permissionDetail: approval?.permissionDetail,
   };
 }