diff --git a/packages/dashboard/package.json b/packages/dashboard/package.json
index b5b5358..62bc08b 100644
--- a/packages/dashboard/package.json
+++ b/packages/dashboard/package.json
@@ -9,6 +9,7 @@
     "preview": "vite preview"
   },
   "dependencies": {
+    "@anthropic-ai/sdk": "^0.78.0",
     "@dagrejs/dagre": "^2.0.4",
     "@monaco-editor/react": "^4.7.0",
     "@understand-anything/core": "workspace:*",
diff --git a/packages/dashboard/src/App.tsx b/packages/dashboard/src/App.tsx
index 61a3c20..6ff1b21 100644
--- a/packages/dashboard/src/App.tsx
+++ b/packages/dashboard/src/App.tsx
@@ -5,6 +5,7 @@ import GraphView from "./components/GraphView";
 import CodeViewer from "./components/CodeViewer";
 import SearchBar from "./components/SearchBar";
 import NodeInfo from "./components/NodeInfo";
+import ChatPanel from "./components/ChatPanel";
 
 function App() {
   const graph = useDashboardStore((s) => s.graph);
@@ -55,9 +56,9 @@ function App() {
           <CodeViewer />
         </div>
 
-        {/* Bottom-left: Chat placeholder */}
-        <div className="min-h-0 min-w-0 bg-gray-800 rounded-lg flex items-center justify-center">
-          <p className="text-gray-400 text-sm">Chat panel (coming soon)</p>
+        {/* Bottom-left: Chat */}
+        <div className="min-h-0 min-w-0">
+          <ChatPanel />
         </div>
 
         {/* Bottom-right: Node Info */}
diff --git a/packages/dashboard/src/components/ChatPanel.tsx b/packages/dashboard/src/components/ChatPanel.tsx
new file mode 100644
index 0000000..5013471
--- /dev/null
+++ b/packages/dashboard/src/components/ChatPanel.tsx
@@ -0,0 +1,180 @@
+import { useEffect, useRef, useState } from "react";
+import { useDashboardStore } from "../store";
+
+export default function ChatPanel() {
+  const graph = useDashboardStore((s) => s.graph);
+  const selectedNodeId = useDashboardStore((s) => s.selectedNodeId);
+  const apiKey = useDashboardStore((s) => s.apiKey);
+  const chatMessages = useDashboardStore((s) => s.chatMessages);
+  const chatLoading = useDashboardStore((s) => s.chatLoading);
+  const setApiKey = useDashboardStore((s) => s.setApiKey);
+  const sendChatMessage = useDashboardStore((s) => s.sendChatMessage);
+  const clearChat = useDashboardStore((s) => s.clearChat);
+
+  const [input, setInput] = useState("");
+  const [keyInput, setKeyInput] = useState("");
+  const messagesEndRef = useRef<HTMLDivElement>(null);
+
+  const selectedNode = graph?.nodes.find((n) => n.id === selectedNodeId);
+
+  // Load API key from localStorage on mount
+  useEffect(() => {
+    const storedKey = localStorage.getItem("ua-api-key");
+    if (storedKey) {
+      setApiKey(storedKey);
+    }
+  }, [setApiKey]);
+
+  // Auto-scroll to latest message
+  useEffect(() => {
+    messagesEndRef.current?.scrollIntoView({ behavior: "smooth" });
+  }, [chatMessages, chatLoading]);
+
+  const handleSend = () => {
+    if (!input.trim() || chatLoading || !apiKey) return;
+    sendChatMessage(input.trim());
+    setInput("");
+  };
+
+  const handleKeyDown = (e: React.KeyboardEvent) => {
+    if (e.key === "Enter" && !e.shiftKey) {
+      e.preventDefault();
+      handleSend();
+    }
+  };
+
+  const handleSetKey = () => {
+    if (keyInput.trim()) {
+      setApiKey(keyInput.trim());
+      setKeyInput("");
+    }
+  };
+
+  const handleKeyInputKeyDown = (e: React.KeyboardEvent) => {
+    if (e.key === "Enter") {
+      e.preventDefault();
+      handleSetKey();
+    }
+  };
+
+  return (
+    <div className="h-full w-full bg-gray-800 rounded-lg flex flex-col overflow-hidden">
+      {/* Header */}
+      <div className="flex items-center justify-between px-3 py-2 border-b border-gray-700 shrink-0">
+        <h3 className="text-xs font-semibold text-gray-400 uppercase tracking-wider">
+          Chat
+        </h3>
+        {chatMessages.length > 0 && (
+          <button
+            onClick={clearChat}
+            className="text-[10px] text-gray-500 hover:text-gray-300 transition-colors"
+          >
+            Clear
+          </button>
+        )}
+      </div>
+
+      {/* API Key Input */}
+      {!apiKey && (
+        <div className="px-3 py-2 border-b border-gray-700 shrink-0">
+          <div className="flex gap-2">
+            <input
+              type="password"
+              value={keyInput}
+              onChange={(e) => setKeyInput(e.target.value)}
+              onKeyDown={handleKeyInputKeyDown}
+              placeholder="Enter Anthropic API key..."
+              className="flex-1 bg-gray-700 text-xs text-white rounded px-2 py-1.5 placeholder-gray-500 outline-none focus:ring-1 focus:ring-blue-500"
+            />
+            <button
+              onClick={handleSetKey}
+              disabled={!keyInput.trim()}
+              className="text-xs bg-blue-600 text-white px-2 py-1.5 rounded hover:bg-blue-500 disabled:opacity-40 disabled:cursor-not-allowed transition-colors"
+            >
+              Set
+            </button>
+          </div>
+        </div>
+      )}
+
+      {/* Context Indicator */}
+      {selectedNode && (
+        <div className="px-3 py-1.5 border-b border-gray-700 shrink-0">
+          <span className="text-[10px] text-gray-500">Context: </span>
+          <span className="text-[10px] text-blue-400">{selectedNode.name}</span>
+        </div>
+      )}
+
+      {/* Messages */}
+      <div className="flex-1 overflow-y-auto px-3 py-2 space-y-2 min-h-0">
+        {chatMessages.length === 0 && (
+          <div className="flex items-center justify-center h-full">
+            <p className="text-gray-500 text-xs text-center">
+              {apiKey
+                ? "Ask anything about this codebase"
+                : "Set your API key to start chatting"}
+            </p>
+          </div>
+        )}
+
+        {chatMessages.map((msg, i) => (
+          <div
+            key={i}
+            className={`flex ${msg.role === "user" ? "justify-end" : "justify-start"}`}
+          >
+            <div
+              className={`max-w-[85%] rounded-lg px-3 py-2 text-xs leading-relaxed whitespace-pre-wrap ${
+                msg.role === "user"
+                  ? "bg-blue-600 text-white"
+                  : "bg-gray-700 text-gray-200"
+              }`}
+            >
+              {msg.content}
+            </div>
+          </div>
+        ))}
+
+        {chatLoading && (
+          <div className="flex justify-start">
+            <div className="bg-gray-700 rounded-lg px-3 py-2 text-xs text-gray-400">
+              <span className="inline-flex gap-1">
+                <span className="animate-pulse">Thinking</span>
+                <span className="animate-pulse delay-100">.</span>
+                <span className="animate-pulse delay-200">.</span>
+                <span className="animate-pulse delay-300">.</span>
+              </span>
+            </div>
+          </div>
+        )}
+
+        <div ref={messagesEndRef} />
+      </div>
+
+      {/* Input */}
+      <div className="px-3 py-2 border-t border-gray-700 shrink-0">
+        <div className="flex gap-2">
+          <input
+            type="text"
+            value={input}
+            onChange={(e) => setInput(e.target.value)}
+            onKeyDown={handleKeyDown}
+            placeholder={
+              apiKey
+                ? "Ask about this codebase..."
+                : "Set API key first"
+            }
+            disabled={!apiKey || chatLoading}
+            className="flex-1 bg-gray-700 text-xs text-white rounded px-2 py-1.5 placeholder-gray-500 outline-none focus:ring-1 focus:ring-blue-500 disabled:opacity-50 disabled:cursor-not-allowed"
+          />
+          <button
+            onClick={handleSend}
+            disabled={!apiKey || chatLoading || !input.trim()}
+            className="text-xs bg-blue-600 text-white px-3 py-1.5 rounded hover:bg-blue-500 disabled:opacity-40 disabled:cursor-not-allowed transition-colors"
+          >
+            Send
+          </button>
+        </div>
+      </div>
+    </div>
+  );
+}
diff --git a/packages/dashboard/src/store.ts b/packages/dashboard/src/store.ts
index 37b8904..5dcdf92 100644
--- a/packages/dashboard/src/store.ts
+++ b/packages/dashboard/src/store.ts
@@ -1,8 +1,14 @@
+import Anthropic from "@anthropic-ai/sdk";
 import { create } from "zustand";
 import { SearchEngine } from "@understand-anything/core/search";
 import type { SearchResult } from "@understand-anything/core/search";
 import type { KnowledgeGraph } from "@understand-anything/core/types";
 
+export interface ChatMessage {
+  role: "user" | "assistant";
+  content: string;
+}
+
 interface DashboardStore {
   graph: KnowledgeGraph | null;
   selectedNodeId: string | null;
@@ -10,9 +16,87 @@ interface DashboardStore {
   searchResults: SearchResult[];
   searchEngine: SearchEngine | null;
 
+  apiKey: string;
+  chatMessages: ChatMessage[];
+  chatLoading: boolean;
+
   setGraph: (graph: KnowledgeGraph) => void;
   selectNode: (nodeId: string | null) => void;
   setSearchQuery: (query: string) => void;
+  setApiKey: (key: string) => void;
+  sendChatMessage: (message: string) => Promise<void>;
+  clearChat: () => void;
+}
+
+function buildSystemPrompt(
+  graph: KnowledgeGraph | null,
+  selectedNodeId: string | null,
+): string {
+  const parts: string[] = [];
+
+  parts.push(
+    "You are an expert code assistant for the Understand Anything dashboard. " +
+      "You help users understand codebases by answering questions about the project structure, " +
+      "code relationships, and architecture. Be concise and helpful.",
+  );
+
+  if (graph) {
+    const { project, nodes, edges, layers } = graph;
+    parts.push(
+      `\n## Project: ${project.name}\n` +
+        `Description: ${project.description}\n` +
+        `Languages: ${project.languages.join(", ")}\n` +
+        `Frameworks: ${project.frameworks.join(", ")}\n` +
+        `Analyzed at: ${project.analyzedAt}`,
+    );
+
+    parts.push(
+      `\n## Graph Overview\n` +
+        `Nodes: ${nodes.length}\n` +
+        `Edges: ${edges.length}\n` +
+        `Layers: ${layers.map((l) => l.name).join(", ") || "none"}`,
+    );
+
+    // Include a summary of all nodes for context
+    const nodeSummaries = nodes
+      .map(
+        (n) =>
+          `- [${n.type}] ${n.name}${n.filePath ? ` (${n.filePath})` : ""}: ${n.summary}`,
+      )
+      .join("\n");
+    parts.push(`\n## All Nodes\n${nodeSummaries}`);
+
+    // Selected node details
+    if (selectedNodeId) {
+      const node = nodes.find((n) => n.id === selectedNodeId);
+      if (node) {
+        const connections = edges.filter(
+          (e) => e.source === node.id || e.target === node.id,
+        );
+        const connDetails = connections
+          .map((e) => {
+            const isSource = e.source === node.id;
+            const otherId = isSource ? e.target : e.source;
+            const otherNode = nodes.find((n) => n.id === otherId);
+            return `  ${isSource ? "->" : "<-"} [${e.type}] ${otherNode?.name ?? otherId}`;
+          })
+          .join("\n");
+
+        parts.push(
+          `\n## Currently Selected Node\n` +
+            `Name: ${node.name}\n` +
+            `Type: ${node.type}\n` +
+            `Summary: ${node.summary}\n` +
+            `File: ${node.filePath ?? "N/A"}\n` +
+            `Tags: ${node.tags.join(", ") || "none"}\n` +
+            `Complexity: ${node.complexity}\n` +
+            `Connections:\n${connDetails || "  none"}`,
+        );
+      }
+    }
+  }
+
+  return parts.join("\n");
 }
 
 export const useDashboardStore = create<DashboardStore>()((set, get) => ({
@@ -22,6 +106,10 @@ export const useDashboardStore = create<DashboardStore>()((set, get) => ({
   searchResults: [],
   searchEngine: null,
 
+  apiKey: "",
+  chatMessages: [],
+  chatLoading: false,
+
   setGraph: (graph) => {
     const searchEngine = new SearchEngine(graph.nodes);
     const query = get().searchQuery;
@@ -38,4 +126,65 @@ export const useDashboardStore = create<DashboardStore>()((set, get) => ({
     const searchResults = engine.search(query);
     set({ searchQuery: query, searchResults });
   },
+
+  setApiKey: (key) => {
+    localStorage.setItem("ua-api-key", key);
+    set({ apiKey: key });
+  },
+
+  sendChatMessage: async (message) => {
+    const { apiKey, chatMessages, graph, selectedNodeId } = get();
+    if (!apiKey || !message.trim()) return;
+
+    const userMessage: ChatMessage = { role: "user", content: message };
+    set({
+      chatMessages: [...chatMessages, userMessage],
+      chatLoading: true,
+    });
+
+    try {
+      const client = new Anthropic({
+        apiKey,
+        dangerouslyAllowBrowser: true,
+      });
+
+      const systemPrompt = buildSystemPrompt(graph, selectedNodeId);
+
+      const response = await client.messages.create({
+        model: "claude-sonnet-4-20250514",
+        max_tokens: 1024,
+        system: systemPrompt,
+        messages: [...chatMessages, userMessage].map((m) => ({
+          role: m.role,
+          content: m.content,
+        })),
+      });
+
+      const assistantContent =
+        response.content[0].type === "text"
+          ? response.content[0].text
+          : "Unable to generate a response.";
+
+      const assistantMessage: ChatMessage = {
+        role: "assistant",
+        content: assistantContent,
+      };
+
+      set((state) => ({
+        chatMessages: [...state.chatMessages, assistantMessage],
+        chatLoading: false,
+      }));
+    } catch (err) {
+      const errorMessage: ChatMessage = {
+        role: "assistant",
+        content: `Error: ${err instanceof Error ? err.message : "Failed to get response. Please check your API key."}`,
+      };
+      set((state) => ({
+        chatMessages: [...state.chatMessages, errorMessage],
+        chatLoading: false,
+      }));
+    }
+  },
+
+  clearChat: () => set({ chatMessages: [] }),
 }));
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 84d6e77..7f8183b 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -45,6 +45,9 @@ importers:
 
   packages/dashboard:
     dependencies:
+      '@anthropic-ai/sdk':
+        specifier: ^0.78.0
+        version: 0.78.0(zod@4.3.6)
       '@dagrejs/dagre':
         specifier: ^2.0.4
         version: 2.0.4
@@ -107,6 +110,15 @@ importers:
 
 packages:
 
+  '@anthropic-ai/sdk@0.78.0':
+    resolution: {integrity: sha512-PzQhR715td/m1UaaN5hHXjYB8Gl2lF9UVhrrGrZeysiF6Rb74Wc9GCB8hzLdzmQtBd1qe89F9OptgB9Za1Ib5w==}
+    hasBin: true
+    peerDependencies:
+      zod: ^3.25.0 || ^4.0.0
+    peerDependenciesMeta:
+      zod:
+        optional: true
+
   '@babel/code-frame@7.29.0':
     resolution: {integrity: sha512-9NhCeYjq9+3uxgdtp20LSiJXJvN0FeCtNGpJxuMFZ1Kv3cWUNb6DOhJwUvcVCzKGR66cw4njwM6hrJLqgOwbcw==}
     engines: {node: '>=6.9.0'}
@@ -178,6 +190,10 @@ packages:
     peerDependencies:
       '@babel/core': ^7.0.0-0
 
+  '@babel/runtime@7.28.6':
+    resolution: {integrity: sha512-05WQkdpL9COIMz4LjTxGpPNCdlpyimKppYNoJ5Di5EUObifl8t4tuLuUBBZEpoLYOmfvIWrsp9fCl0HoPRVTdA==}
+    engines: {node: '>=6.9.0'}
+
   '@babel/template@7.28.6':
     resolution: {integrity: sha512-YA6Ma2KsCdGb+WC6UpBVFJGXL58MDA6oyONbjyF/+5sBgxY/dwkhLogbMT2GXXyU84/IhRw/2D1Os1B/giz+BQ==}
     engines: {node: '>=6.9.0'}
@@ -1019,6 +1035,10 @@ packages:
     engines: {node: '>=6'}
     hasBin: true
 
+  json-schema-to-ts@3.1.1:
+    resolution: {integrity: sha512-+DWg8jCJG2TEnpy7kOm/7/AxaYoaRbjVB4LFZLySZlWn8exGs3A4OLJR966cVvU26N7X9TWxl+Jsw7dzAqKT6g==}
+    engines: {node: '>=16'}
+
   json5@2.2.3:
     resolution: {integrity: sha512-XmOWe7eyHYH14cLdVPoyg+GOH3rYX++KpzrylJwSW98t3Nk+U8XOl8FWKOgwtzdb8lXGf6zYwDUzeHMWfxasyg==}
     engines: {node: '>=6'}
@@ -1245,6 +1265,9 @@ packages:
       tree-sitter:
         optional: true
 
+  ts-algebra@2.0.0:
+    resolution: {integrity: sha512-FPAhNPFMrkwz76P7cdjdmiShwMynZYN6SgOujD1urY4oNm80Ou9oMdmbR45LotcKOXoy7wSmHkRFE6Mxbrhefw==}
+
   typescript@5.9.3:
     resolution: {integrity: sha512-jl1vZzPDinLr9eUt3J/t7V6FgNEw9QjvBPdysz9KfQDD41fQrC2Y4vKQdiaUpFT4bXlb1RHhLpp8wtm6M5TgSw==}
     engines: {node: '>=14.17'}
@@ -1429,6 +1452,12 @@ packages:
 
 snapshots:
 
+  '@anthropic-ai/sdk@0.78.0(zod@4.3.6)':
+    dependencies:
+      json-schema-to-ts: 3.1.1
+    optionalDependencies:
+      zod: 4.3.6
+
   '@babel/code-frame@7.29.0':
     dependencies:
       '@babel/helper-validator-identifier': 7.28.5
@@ -1518,6 +1547,8 @@ snapshots:
       '@babel/core': 7.29.0
       '@babel/helper-plugin-utils': 7.28.6
 
+  '@babel/runtime@7.28.6': {}
+
   '@babel/template@7.28.6':
     dependencies:
       '@babel/code-frame': 7.29.0
@@ -1968,14 +1999,6 @@ snapshots:
       chai: 5.3.3
       tinyrainbow: 2.0.0
 
-  '@vitest/mocker@3.2.4(vite@7.3.1(@types/node@22.19.15)(jiti@2.6.1)(lightningcss@1.31.1))':
-    dependencies:
-      '@vitest/spy': 3.2.4
-      estree-walker: 3.0.3
-      magic-string: 0.30.21
-    optionalDependencies:
-      vite: 7.3.1(@types/node@22.19.15)(jiti@2.6.1)(lightningcss@1.31.1)
-
   '@vitest/mocker@3.2.4(vite@7.3.1(@types/node@25.5.0)(jiti@2.6.1)(lightningcss@1.31.1))':
     dependencies:
       '@vitest/spy': 3.2.4
@@ -2209,6 +2232,11 @@ snapshots:
 
   jsesc@3.1.0: {}
 
+  json-schema-to-ts@3.1.1:
+    dependencies:
+      '@babel/runtime': 7.28.6
+      ts-algebra: 2.0.0
+
   json5@2.2.3: {}
 
   lightningcss-android-arm64@1.31.1:
@@ -2394,6 +2422,8 @@ snapshots:
       node-gyp-build: 4.8.4
       tree-sitter-javascript: 0.23.1
 
+  ts-algebra@2.0.0: {}
+
   typescript@5.9.3: {}
 
   undici-types@6.21.0: {}
@@ -2512,7 +2542,7 @@ snapshots:
     dependencies:
       '@types/chai': 5.2.3
       '@vitest/expect': 3.2.4
-      '@vitest/mocker': 3.2.4(vite@7.3.1(@types/node@22.19.15)(jiti@2.6.1)(lightningcss@1.31.1))
+      '@vitest/mocker': 3.2.4(vite@7.3.1(@types/node@25.5.0)(jiti@2.6.1)(lightningcss@1.31.1))
       '@vitest/pretty-format': 3.2.4
       '@vitest/runner': 3.2.4
       '@vitest/snapshot': 3.2.4