diff --git a/ui/jest.setup.ts b/ui/jest.setup.ts
index be96e4bc92..32d27029c9 100644
--- a/ui/jest.setup.ts
+++ b/ui/jest.setup.ts
@@ -31,6 +31,22 @@ global.ResizeObserver = class ResizeObserver {
 // jsdom: cmdk scrolls selected items into view
 Element.prototype.scrollIntoView = function scrollIntoView() {};
 
+// jsdom: SidebarProvider / useIsMobile
+Object.defineProperty(window, "matchMedia", {
+  writable: true,
+  configurable: true,
+  value: jest.fn().mockImplementation((query: string) => ({
+    matches: false,
+    media: query,
+    onchange: null,
+    addListener: jest.fn(),
+    removeListener: jest.fn(),
+    addEventListener: jest.fn(),
+    removeEventListener: jest.fn(),
+    dispatchEvent: jest.fn(),
+  })),
+});
+
 // Mock next/router
 jest.mock('next/router', () => ({
   useRouter() {
diff --git a/ui/src/components/chat/ChatInterface.tsx b/ui/src/components/chat/ChatInterface.tsx
index 6c055ae144..ac43cc34d6 100644
--- a/ui/src/components/chat/ChatInterface.tsx
+++ b/ui/src/components/chat/ChatInterface.tsx
@@ -911,7 +911,7 @@ export default function ChatInterface({ selectedAgentName, selectedNamespace, se
     );
   }
   return (
-    <div className="w-full h-screen flex flex-col justify-center min-w-full items-center transition-all duration-300 ease-in-out">
+    <div className="flex h-screen w-full min-w-0 flex-col items-center justify-center transition-all duration-300 ease-in-out">
       <div className="flex-1 w-full overflow-hidden relative">
         <ScrollArea ref={containerRef} className="w-full h-full py-12">
           <div className="flex flex-col space-y-5 px-4">
diff --git a/ui/src/components/chat/ChatLayoutUI.tsx b/ui/src/components/chat/ChatLayoutUI.tsx
index 2a239c94f0..8bcaa845c3 100644
--- a/ui/src/components/chat/ChatLayoutUI.tsx
+++ b/ui/src/components/chat/ChatLayoutUI.tsx
@@ -108,17 +108,18 @@ export default function ChatLayoutUI({
         agentSessions={sessions}
         isLoadingSessions={isLoadingSessions}
       />
-      <main className="w-full max-w-6xl mx-auto px-4">
-        <ChatAgentProvider
-          agentType={currentAgent.agent.spec.type}
-          runInSandbox={currentAgent.workloadMode === "sandbox"}
-          substrateSandbox={isSubstrateSandboxAgent(currentAgent)}
-        >
-          {children}
-        </ChatAgentProvider>
+      <main className="flex min-h-svh min-w-0 flex-1 flex-col overflow-x-hidden px-4">
+        <div className="mx-auto flex w-full min-w-0 max-w-6xl flex-1 flex-col">
+          <ChatAgentProvider
+            agentType={currentAgent.agent.spec.type}
+            runInSandbox={currentAgent.workloadMode === "sandbox"}
+            substrateSandbox={isSubstrateSandboxAgent(currentAgent)}
+          >
+            {children}
+          </ChatAgentProvider>
+        </div>
       </main>
       <AgentDetailsSidebar
-        selectedAgentName={agentName}
         currentAgent={currentAgent}
         allTools={convertedTools}
       />
diff --git a/ui/src/components/sidebars/AgentDetailsSidebar.stories.tsx b/ui/src/components/sidebars/AgentDetailsSidebar.stories.tsx
index 5758051984..721a1779ba 100644
--- a/ui/src/components/sidebars/AgentDetailsSidebar.stories.tsx
+++ b/ui/src/components/sidebars/AgentDetailsSidebar.stories.tsx
@@ -154,7 +154,6 @@ const mockTools: ToolsResponse[] = [
 
 export const AgentWithTools: Story = {
   args: {
-    selectedAgentName: "kagent/momus-gpt",
     currentAgent: mockAgent,
     allTools: mockTools,
   },
@@ -162,7 +161,6 @@ export const AgentWithTools: Story = {
 
 export const AgentWithNoTools: Story = {
   args: {
-    selectedAgentName: "kagent/simple-agent",
     currentAgent: mockAgentNoTools,
     allTools: [],
   },
@@ -170,7 +168,6 @@ export const AgentWithNoTools: Story = {
 
 export const BYOAgent: Story = {
   args: {
-    selectedAgentName: "kagent/custom-agent",
     currentAgent: mockBYOAgent,
     allTools: [],
   },
diff --git a/ui/src/components/sidebars/AgentDetailsSidebar.tsx b/ui/src/components/sidebars/AgentDetailsSidebar.tsx
index 0d877ed290..065f85cced 100644
--- a/ui/src/components/sidebars/AgentDetailsSidebar.tsx
+++ b/ui/src/components/sidebars/AgentDetailsSidebar.tsx
@@ -17,12 +17,11 @@ import { Tooltip, TooltipContent, TooltipProvider, TooltipTrigger } from "@/comp
 import { Badge } from "@/components/ui/badge";
 
 interface AgentDetailsSidebarProps {
-  selectedAgentName: string;
   currentAgent: AgentResponse;
   allTools: ToolsResponse[];
 }
 
-export function AgentDetailsSidebar({ selectedAgentName, currentAgent, allTools }: AgentDetailsSidebarProps) {
+export function AgentDetailsSidebar({ currentAgent, allTools }: AgentDetailsSidebarProps) {
   const [toolDescriptions, setToolDescriptions] = useState<Record<string, string>>({});
   const [expandedTools, setExpandedTools] = useState<Record<string, boolean>>({});
   const [availableAgents, setAvailableAgents] = useState<AgentResponse[]>([]);
@@ -233,28 +232,47 @@ export function AgentDetailsSidebar({ selectedAgentName, currentAgent, allTools
   // Declarative agents (including SandboxAgent with declarative spec) share model-backed config.
   const isDeclarativeLikeAgent = selectedTeam?.agent.spec.type === "Declarative";
 
+  const agentNamespace = selectedTeam.agent.metadata.namespace ?? "";
+  const agentName = selectedTeam.agent.metadata.name ?? "";
+  const agentRef = `${agentNamespace}/${agentName}`;
+  const editHref = `/agents/new?${new URLSearchParams({
+    edit: "true",
+    name: agentName,
+    namespace: agentNamespace,
+  }).toString()}`;
+
   return (
     <>
       <Sidebar side={"right"} collapsible="offcanvas">
-        <SidebarHeader>Agent Details</SidebarHeader>
+        <SidebarHeader className="flex flex-row items-center justify-between gap-2">
+          <span className="text-sm font-semibold leading-none">Agent Details</span>
+          <Button
+            variant="ghost"
+            size="icon"
+            className="h-7 w-7 shrink-0"
+            asChild
+            aria-label={`Edit agent ${agentRef}`}
+          >
+            <Link href={editHref}>
+              <Edit className="h-3.5 w-3.5" />
+            </Link>
+          </Button>
+        </SidebarHeader>
         <SidebarContent>
           <ScrollArea>
             <SidebarGroup>
-              <div className="flex items-center justify-between px-2 mb-1">
-                <SidebarGroupLabel className="font-bold mb-0 p-0">
-                  {selectedTeam?.agent.metadata.namespace}/{selectedTeam?.agent.metadata.name} {selectedTeam?.model && `(${selectedTeam?.model})`}
-                </SidebarGroupLabel>
-                <Button
-                  variant="ghost"
-                  size="icon"
-                  className="h-7 w-7"
-                  asChild
-                  aria-label={`Edit agent ${selectedTeam?.agent.metadata.namespace}/${selectedTeam?.agent.metadata.name}`}
+              <div className="min-w-0 px-2 mb-1">
+                <SidebarGroupLabel
+                  className="font-bold mb-0 block w-full truncate p-0"
+                  title={selectedTeam?.model ? `${agentRef} (${selectedTeam.model})` : agentRef}
                 >
-                  <Link href={`/agents/new?edit=true&name=${selectedAgentName}&namespace=${currentAgent.agent.metadata.namespace}`}>
-                    <Edit className="h-3.5 w-3.5" />
-                  </Link>
-                </Button>
+                  {agentRef}
+                </SidebarGroupLabel>
+                {selectedTeam?.model && (
+                  <p className="mt-0.5 truncate text-xs text-muted-foreground" title={selectedTeam.model}>
+                    {selectedTeam.model}
+                  </p>
+                )}
               </div>
               <p className="text-sm flex px-2 text-muted-foreground">{selectedTeam?.agent.spec.description}</p>
             </SidebarGroup>
diff --git a/ui/src/components/sidebars/__tests__/AgentDetailsSidebar.test.tsx b/ui/src/components/sidebars/__tests__/AgentDetailsSidebar.test.tsx
new file mode 100644
index 0000000000..44e65c9381
--- /dev/null
+++ b/ui/src/components/sidebars/__tests__/AgentDetailsSidebar.test.tsx
@@ -0,0 +1,74 @@
+/**
+ * @jest-environment jsdom
+ */
+import { render, screen } from "@testing-library/react";
+import { AgentDetailsSidebar } from "@/components/sidebars/AgentDetailsSidebar";
+import { SidebarProvider } from "@/components/ui/sidebar";
+import type { AgentResponse } from "@/types";
+
+jest.mock("@/app/actions/agents", () => ({
+  getAgents: jest.fn().mockResolvedValue({ data: [] }),
+}));
+
+function renderSidebar(currentAgent: AgentResponse) {
+  return render(
+    <SidebarProvider defaultOpen>
+      <AgentDetailsSidebar
+        currentAgent={currentAgent}
+        allTools={[]}
+      />
+    </SidebarProvider>,
+  );
+}
+
+const longNameAgent: AgentResponse = {
+  id: 1,
+  agent: {
+    metadata: {
+      name: "test-my-agent-qwen7b",
+      namespace: "ak-poc-testing",
+    },
+    spec: {
+      description: "testing me agent bro",
+      type: "Declarative",
+    },
+  },
+  model: "vllm/Qwen/Qwen2.5-7B-Instruct",
+  modelProvider: "openai",
+  modelConfigRef: "ak-poc-testing/qwen7b",
+  deploymentReady: true,
+  accepted: true,
+  tools: [
+    {
+      type: "Agent",
+      agent: {
+        name: "k8s-agent",
+        namespace: "ak-poc-testing",
+        kind: "Agent",
+        apiGroup: "kagent.dev",
+      },
+    },
+  ],
+};
+
+describe("AgentDetailsSidebar", () => {
+  it("shows the edit control in the header for agents with long names and model strings", () => {
+    renderSidebar(longNameAgent);
+
+    const editLink = screen.getByRole("link", {
+      name: "Edit agent ak-poc-testing/test-my-agent-qwen7b",
+    });
+    expect(editLink).toBeInTheDocument();
+    expect(editLink).toHaveAttribute(
+      "href",
+      "/agents/new?edit=true&name=test-my-agent-qwen7b&namespace=ak-poc-testing",
+    );
+  });
+
+  it("renders agent ref and model on separate truncated lines", () => {
+    renderSidebar(longNameAgent);
+
+    expect(screen.getByText("ak-poc-testing/test-my-agent-qwen7b")).toBeInTheDocument();
+    expect(screen.getByText("vllm/Qwen/Qwen2.5-7B-Instruct")).toBeInTheDocument();
+  });
+});