Release 0.5.14 (#608)

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

.changeset/calm-women-repair.md

@@ -1,5 +0,0 @@
----
-"create-llama": patch
----
-
-Split artifacts use case to document generator and code generator

.changeset/fifty-badgers-jog.md

@@ -1,5 +0,0 @@
----
-"create-llama": patch
----
-
-Fix typing check issue

.changeset/five-buses-bake.md

@@ -1,5 +0,0 @@
----
-"create-llama": patch
----
-
-fix chromadb dependency issue

.changeset/silent-ladybugs-hear.md

@@ -1,5 +0,0 @@
----
-"create-llama": patch
----
-
-fix: remove dead generated ai code

.changeset/tired-regions-notice.md

@@ -1,5 +0,0 @@
----
-"create-llama": patch
----
-
-Deprecate pro mode

.github/workflows/e2e.yml

@@ -79,7 +79,7 @@ jobs:
       - uses: actions/upload-artifact@v4
         if: always()
         with:
-          name: playwright-report-python-${{ matrix.os }}-${{ matrix.frameworks }}-${{ matrix.datasources }}
+          name: playwright-report-python-${{ matrix.os }}-${{ matrix.frameworks }}-${{ matrix.datasources }}-${{ matrix.template-types }}
           path: packages/create-llama/playwright-report/
           overwrite: true
           retention-days: 30
@@ -149,7 +149,7 @@ jobs:
       - uses: actions/upload-artifact@v4
         if: always()
         with:
-          name: playwright-report-typescript-${{ matrix.os }}-${{ matrix.frameworks }}-${{ matrix.datasources }}-node${{ matrix.node-version }}
+          name: playwright-report-typescript-${{ matrix.os }}-${{ matrix.frameworks }}-${{ matrix.datasources }}-node${{ matrix.node-version }}-${{ matrix.template-types }}
           path: packages/create-llama/playwright-report/
           overwrite: true
           retention-days: 30

packages/create-llama/CHANGELOG.md

@@ -1,5 +1,16 @@
 # create-llama
 
+## 0.5.14
+
+### Patch Changes
+
+- 1df8cfb: Split artifacts use case to document generator and code generator
+- 1b5a519: chore: improve dev experience with nodemon
+- b3eb0ba: Fix typing check issue
+- 556f33c: fix chromadb dependency issue
+- 2451539: fix: remove dead generated ai code
+- 7a70390: Deprecate pro mode
+
 ## 0.5.13
 
 ### Patch Changes

packages/create-llama/package.json

@@ -1,6 +1,6 @@
 {
   "name": "create-llama",
-  "version": "0.5.13",
+  "version": "0.5.14",
   "description": "Create LlamaIndex-powered apps with one command",
   "keywords": [
     "rag",

packages/create-llama/templates/components/use-cases/typescript/code_generator/src/app/workflow.ts

@@ -1,5 +1,5 @@
 import { extractLastArtifact } from "@llamaindex/server";
-import { ChatMemoryBuffer, LLM, MessageContent, Settings } from "llamaindex";
+import { ChatMemoryBuffer, MessageContent, Settings } from "llamaindex";
 
 import {
   agentStreamEvent,
@@ -12,12 +12,6 @@ import {
 
 import { z } from "zod";
 
-export const workflowFactory = async (reqBody: any) => {
-  const workflow = createCodeArtifactWorkflow(reqBody);
-
-  return workflow;
-};
-
 export const RequirementSchema = z.object({
   next_step: z.enum(["answering", "coding"]),
   language: z.string().nullable().optional(),
@@ -71,32 +65,28 @@ const artifactEvent = workflowEvent<{
   };
 }>();
 
-export function createCodeArtifactWorkflow(reqBody: any, llm?: LLM) {
-  if (!llm) {
-    llm = Settings.llm;
-  }
+export function workflowFactory(reqBody: any) {
+  const llm = Settings.llm;
+
   const { withState, getContext } = createStatefulMiddleware(() => {
     return {
-      memory: new ChatMemoryBuffer({
-        llm,
-        chatHistory: reqBody.chatHistory,
-      }),
+      memory: new ChatMemoryBuffer({ llm }),
       lastArtifact: extractLastArtifact(reqBody),
     };
   });
   const workflow = withState(createWorkflow());
 
-  workflow.handle([startAgentEvent], async ({ data: { userInput } }) => {
+  workflow.handle([startAgentEvent], async ({ data }) => {
+    const { userInput, chatHistory = [] } = data;
     // Prepare chat history
     const { state } = getContext();
     // Put user input to the memory
     if (!userInput) {
       throw new Error("Missing user input to start the workflow");
     }
-    state.memory.put({
-      role: "user",
-      content: userInput,
-    });
+    state.memory.set(chatHistory);
+    state.memory.put({ role: "user", content: userInput });
+
     return planEvent.with({
       userInput: userInput,
     });

packages/create-llama/templates/components/use-cases/typescript/document_generator/src/app/workflow.ts

@@ -1,5 +1,5 @@
 import { extractLastArtifact } from "@llamaindex/server";
-import { ChatMemoryBuffer, LLM, MessageContent, Settings } from "llamaindex";
+import { ChatMemoryBuffer, MessageContent, Settings } from "llamaindex";
 
 import {
   agentStreamEvent,
@@ -12,12 +12,6 @@ import {
 
 import { z } from "zod";
 
-export const workflowFactory = async (reqBody: any) => {
-  const workflow = createDocumentArtifactWorkflow(reqBody);
-
-  return workflow;
-};
-
 export const DocumentRequirementSchema = z.object({
   type: z.enum(["markdown", "html"]),
   title: z.string(),
@@ -74,32 +68,28 @@ const artifactEvent = workflowEvent<{
   };
 }>();
 
-export function createDocumentArtifactWorkflow(reqBody: any, llm?: LLM) {
-  if (!llm) {
-    llm = Settings.llm;
-  }
+export function workflowFactory(reqBody: any) {
+  const llm = Settings.llm;
+
   const { withState, getContext } = createStatefulMiddleware(() => {
     return {
-      memory: new ChatMemoryBuffer({
-        llm,
-        chatHistory: reqBody.chatHistory,
-      }),
+      memory: new ChatMemoryBuffer({ llm }),
       lastArtifact: extractLastArtifact(reqBody),
     };
   });
   const workflow = withState(createWorkflow());
 
-  workflow.handle([startAgentEvent], async ({ data: { userInput } }) => {
+  workflow.handle([startAgentEvent], async ({ data }) => {
+    const { userInput, chatHistory = [] } = data;
     // Prepare chat history
     const { state } = getContext();
     // Put user input to the memory
     if (!userInput) {
       throw new Error("Missing user input to start the workflow");
     }
-    state.memory.put({
-      role: "user",
-      content: userInput,
-    });
+    state.memory.set(chatHistory);
+    state.memory.put({ role: "user", content: userInput });
+
     return planEvent.with({
       userInput,
       context: state.lastArtifact

packages/create-llama/templates/types/llamaindexserver/nextjs/nodemon.json

@@ -0,0 +1,6 @@
+{
+  "watch": ["src/**/*.ts"],
+  "exec": "nodemon --exec tsx src/index.ts",
+  "ext": "js ts",
+  "ignore": ["src/app/workflow_*.ts"]
+}

packages/create-llama/templates/types/llamaindexserver/nextjs/package.json

@@ -5,7 +5,7 @@
     "generate": "tsx src/generate.ts datasource",
     "generate:datasource": "tsx src/generate.ts datasource",
     "generate:ui": "tsx src/generate.ts ui",
-    "dev": "tsx watch src/index.ts",
+    "dev": "nodemon",
     "start": "tsx src/index.ts"
   },
   "dependencies": {
@@ -20,6 +20,7 @@
   "devDependencies": {
     "@types/node": "^20.10.3",
     "tsx": "^4.7.2",
-    "typescript": "^5.3.2"
+    "typescript": "^5.3.2",
+    "nodemon": "^3.1.10"
   }
 }

packages/server/CHANGELOG.md

@@ -1,5 +1,11 @@
 # @llamaindex/server
 
+## 0.2.1
+
+### Patch Changes
+
+- f072308: feat: add dev mode UI
+
 ## 0.2.0
 
 ### Minor Changes

packages/server/README.md

@@ -4,10 +4,10 @@ LlamaIndexServer is a Next.js-based application that allows you to quickly launc
 
 ## Features
 
-- Serving a workflow as a chatbot
+- Add a sophisticated chatbot UI to your LlamaIndex workflow
+- Edit code and document artifacts in an OpenAI Canvas-style UI
+- Extendable UI components for events and headers
 - Built on Next.js for high performance and easy API development
-- Optional built-in chat UI with extendable UI components
-- Prebuilt development code
 
 ## Installation
 
@@ -21,9 +21,11 @@ Create an `index.ts` file and add the following code:
 
 ```ts
 import { LlamaIndexServer } from "@llamaindex/server";
+import { openai } from "@llamaindex/openai";
+import { agent } from "@llamaindex/workflow";
 import { wiki } from "@llamaindex/tools"; // or any other tool
 
-const createWorkflow = () => agent({ tools: [wiki()] });
+const createWorkflow = () => agent({ tools: [wiki()], llm: openai("gpt-4o") });
 
 new LlamaIndexServer({
   workflow: createWorkflow,
@@ -34,6 +36,8 @@ new LlamaIndexServer({
 }).start();
 ```
 
+The `createWorkflow` function is a factory function that creates an [Agent Workflow](https://ts.llamaindex.ai/docs/llamaindex/modules/agents/agent_workflow) with a tool that retrieves information from Wikipedia in this case. For more details, read about the [Workflow factory contract](#workflow-factory-contract).
+
 ## Running the Server
 
 In the same directory as `index.ts`, run the following command to start the server:
@@ -54,16 +58,75 @@ curl -X POST "http://localhost:3000/api/chat" -H "Content-Type: application/json
 
 The `LlamaIndexServer` accepts the following configuration options:
 
-- `workflow`: A callable function that creates a workflow instance for each request
+- `workflow`: A callable function that creates a workflow instance for each request. See [Workflow factory contract](#workflow-factory-contract) for more details.
 - `uiConfig`: An object to configure the chat UI containing the following properties:
   - `appTitle`: The title of the application (default: `"LlamaIndex App"`)
   - `starterQuestions`: List of starter questions for the chat UI (default: `[]`)
   - `componentsDir`: The directory for custom UI components rendering events emitted by the workflow. The default is undefined, which does not render custom UI components.
   - `llamaCloudIndexSelector`: Whether to show the LlamaCloud index selector in the chat UI (requires `LLAMA_CLOUD_API_KEY` to be set in the environment variables) (default: `false`)
+  - `dev_mode`: When enabled, you can update workflow code in the UI and see the changes immediately. It's currently in beta and only supports updating workflow code at `app/src/workflow.ts`. Please start server in dev mode (`npm run dev`) to use see this reload feature enabled.
 
 LlamaIndexServer accepts all the configuration options from Nextjs Custom Server such as `port`, `hostname`, `dev`, etc.
 See all Nextjs Custom Server options [here](https://nextjs.org/docs/app/building-your-application/configuring/custom-server).
 
+## Workflow factory contract
+
+The `workflow` provided will be called for each chat request to initialize a new workflow instance. The contract of the generated workflow must be the same as for the [Agent Workflow](https://ts.llamaindex.ai/docs/llamaindex/modules/agents/agent_workflow).
+
+This means that the workflow must handle a `startAgentEvent` event, which is the entry point of the workflow and contains the following information in it's `data` property:
+
+```typescript
+{
+  userInput: MessageContent;
+  chatHistory?: ChatMessage[] | undefined;
+};
+```
+
+The `userInput` is the latest user message and the `chatHistory` is the list of messages exchanged between the user and the workflow so far.
+
+Furthermore, the workflow must stop with a `stopAgentEvent` event to mark the end of the workflow. In between, the workflow can emit [UI events](##AI-generated-UI-Components) to render custom UI components and [Artifact events](##Sending-Artifacts-to-the-UI) to send structured data like generated documents or code snippets to the UI.
+
+```ts
+import {
+  createStatefulMiddleware,
+  createWorkflow,
+  startAgentEvent,
+} from "@llamaindex/workflow";
+import { ChatMemoryBuffer, type ChatMessage, Settings } from "llamaindex";
+import { openai } from "@llamaindex/openai";
+import { wiki } from "@llamaindex/tools";
+
+Settings.llm = openai("gpt-4o");
+
+export const workflowFactory = async () => {
+  const workflow = createWorkflow();
+
+  workflow.handle([startAgentEvent], async ({ data }) => {
+    const { state, sendEvent } = getContext();
+    const messages = data.chatHistory;
+
+    const toolCallResponse = await chatWithTools(
+      Settings.llm,
+      [wiki()],
+      messages,
+    );
+
+    // using result from tool call and use `sendEvent` to emit the next event...
+  });
+
+  // define more workflow handling logic here...
+
+  // Finally stop with a `stopAgentEvent` event to mark the end of the workflow.
+  // return stopAgentEvent.with({
+  //   result: "This is the end!",
+  // });
+
+  return workflow;
+};
+```
+
+To generate sophisticated examples of workflows, you best use the [create-llama](https://github.com/run-llama/create-llama) project.
+
 ## AI-generated UI Components
 
 The LlamaIndex server provides support for rendering workflow events using custom UI components, allowing you to extend and customize the chat interface.
@@ -137,6 +200,66 @@ new LlamaIndexServer({
 }).start();
 ```
 
+## Sending Artifacts to the UI
+
+In addition to UI events for custom components, LlamaIndex Server supports a special `ArtifactEvent` to send structured data like generated documents or code snippets to the UI. These artifacts are displayed in a dedicated "Canvas" panel in the chat interface.
+
+### Artifact Event Structure
+
+To send an artifact, your workflow needs to emit an event with `type: "artifact"`. The `data` payload of this event should include:
+
+- `type`: A string indicating the type of artifact (e.g., `"document"`, `"code"`).
+- `created_at`: A timestamp (e.g., `Date.now()`) indicating when the artifact was created.
+- `data`: An object containing the specific details of the artifact. The structure of this object depends on the artifact `type`.
+
+### Defining and Sending an ArtifactEvent
+
+First, define your artifact event using `workflowEvent` from `@llamaindex/workflow`:
+
+```typescript
+import { workflowEvent } from "@llamaindex/workflow";
+
+// Example for a document artifact
+const artifactEvent = workflowEvent<{
+  type: "artifact"; // Must be "artifact"
+  data: {
+    type: "document"; // Custom type for your artifact (e.g., "document", "code")
+    created_at: number;
+    data: {
+      // Specific data for the document artifact type
+      title: string;
+      content: string;
+      type: "markdown" | "html"; // document format
+    };
+  };
+}>();
+```
+
+Then, within your workflow logic, use `sendEvent` (obtained from `getContext()`) to emit the event:
+
+```typescript
+// Assuming 'sendEvent' is available in your workflow handler
+// and 'documentDetails' contains the content for the artifact.
+
+sendEvent(
+  artifactEvent.with({
+    type: "artifact", // This top-level type must be "artifact"
+    data: {
+      type: "document", // This is your specific artifact type
+      created_at: Date.now(),
+      data: {
+        title: "My Generated Document",
+        content: "# Hello World
+This is a markdown document.",
+        type: "markdown",
+      },
+    },
+  }),
+);
+```
+
+This will send the artifact to the LlamaIndex Server UI, where it will be rendered in the [ChatCanvasPanel](/packages/server/next/app/components/ui/chat/canvas/panel.tsx) by a renderer depending on the artifact type. For type `document` this is using the [DocumentArtifactViewer](https://github.com/run-llama/chat-ui/blob/bacb75fc6edceacf742fba18632404a2483b5a81/packages/chat-ui/src/chat/canvas/artifacts/document.tsx#L17).
+
 ## Default Endpoints and Features
 
 ### Chat Endpoint

packages/server/examples/README.md

@@ -6,7 +6,7 @@ This directory contains examples of how to use the LlamaIndex Server.
 
 ```bash
 export OPENAI_API_KEY=your_openai_api_key
-npx tsx simple-workflow/calculator.ts
+pnpm run dev
 ```
 
 ## Open browser at http://localhost:3000

packages/server/examples/agentic-rag/index.ts

@@ -39,5 +39,5 @@ new LlamaIndexServer({
     appTitle: "LlamaIndex App",
     starterQuestions: ["What is the color of the dog?"],
   },
-  port: 4100,
+  port: 3000,
 }).start();

packages/server/examples/devmode/README.md

@@ -0,0 +1,21 @@
+This example shows how to use the dev mode of the server.
+
+First, we need to set `devMode` to `true` in the `uiConfig` of the server.
+
+```ts
+new LlamaIndexServer({
+  workflow: workflowFactory,
+  uiConfig: {
+    appTitle: "Calculator",
+    devMode: true,
+  },
+  port: 3000,
+}).start();
+```
+
+Export OpenAI API key and start the server in dev mode.
+
+```bash
+export OPENAI_API_KEY=<your-openai-api-key>
+npx nodemon --exec tsx index.ts
+```

packages/server/examples/devmode/index.ts

@@ -0,0 +1,15 @@
+import { LlamaIndexServer } from "@llamaindex/server";
+import { workflowFactory } from "./src/app/workflow";
+
+new LlamaIndexServer({
+  workflow: workflowFactory,
+  uiConfig: {
+    appTitle: "Calculator",
+    devMode: true,
+    starterQuestions: [
+      "What is the weather in Tokyo?",
+      "What is the weather in New York?",
+    ],
+  },
+  port: 3000,
+}).start();

packages/server/examples/devmode/src/app/workflow.ts

@@ -0,0 +1,16 @@
+import { agent } from "@llamaindex/workflow";
+import { tool } from "llamaindex";
+import { z } from "zod";
+
+export const workflowFactory = async () => {
+  return agent({
+    tools: [
+      tool({
+        name: "weather",
+        description: "Get the weather in a specific city",
+        parameters: z.object({ city: z.string() }),
+        execute: ({ city }) => `The weather in ${city} is sunny`,
+      }),
+    ],
+  });
+};

packages/server/examples/package.json

@@ -4,7 +4,7 @@
   "private": true,
   "scripts": {
     "typecheck": "tsc --noEmit",
-    "dev": "tsx simple-workflow/calculator.ts"
+    "dev": "nodemon --exec tsx simple-workflow/calculator.ts"
   },
   "dependencies": {
     "@llamaindex/openai": "^0.2.0",
@@ -18,6 +18,7 @@
   },
   "devDependencies": {
     "@types/node": "^20.10.3",
+    "nodemon": "^3.1.10",
     "tsx": "^4.7.2",
     "typescript": "^5.3.2"
   }

packages/server/examples/simple-workflow/calculator.ts

@@ -20,5 +20,5 @@ new LlamaIndexServer({
     appTitle: "Calculator",
     starterQuestions: ["1 + 1", "2 + 2"],
   },
-  port: 4000,
+  port: 3000,
 }).start();

packages/server/next/app/components/ui/chat/chat-section.tsx

@@ -13,6 +13,7 @@ import CustomChatMessages from "./chat-messages";
 import { DynamicEventsErrors } from "./custom/events/dynamic-events-errors";
 import { fetchComponentDefinitions } from "./custom/events/loader";
 import { ComponentDef } from "./custom/events/types";
+import { DevModePanel } from "./dev-mode-panel";
 
 export default function ChatSection() {
   const handler = useChat({
@@ -35,12 +36,13 @@ export default function ChatSection() {
         <ChatHeader />
         <ChatUI
           handler={handler}
-          className="flex min-h-0 flex-1 flex-row justify-center gap-4 px-4 py-0"
+          className="relative flex min-h-0 flex-1 flex-row justify-center gap-4 px-4 py-0"
         >
           <ResizablePanelGroup direction="horizontal">
             <ChatSectionPanel />
             <ChatCanvasPanel />
           </ResizablePanelGroup>
+          <DevModePanel />
         </ChatUI>
       </div>
       <ChatInjection />

packages/server/next/app/components/ui/chat/dev-mode-panel.tsx

@@ -0,0 +1,270 @@
+"use client";
+
+import {
+  CodeEditor,
+  fileExtensionToEditorLang,
+} from "@llamaindex/chat-ui/widgets";
+import { AlertCircle, Loader2 } from "lucide-react";
+import { useEffect, useState } from "react";
+import { Button } from "../button";
+import { getConfig } from "../lib/utils";
+
+const API_PATH = "/api/dev/files/workflow";
+const POLLING_TIMEOUT = 30_000; // 30 seconds
+
+type WorkflowFile = {
+  last_modified: number;
+  file_path: string;
+  content: string;
+};
+
+export function DevModePanel() {
+  const devModeEnabled = getConfig("DEV_MODE");
+  if (!devModeEnabled) return null;
+  return <DevModePanelComp />;
+}
+
+function DevModePanelComp() {
+  const [devModeOpen, setDevModeOpen] = useState(false);
+
+  const [isFetching, setIsFetching] = useState(false);
+  const [fetchingError, setFetchingError] = useState<string | null>();
+  const [workflowFile, setWorkflowFile] = useState<WorkflowFile | null>(null);
+
+  const [updatedCode, setUpdatedCode] = useState<string | null>(null);
+  const [isSaving, setIsSaving] = useState(false);
+  const [saveError, setSaveError] = useState<string | null>(null);
+
+  const [isPolling, setIsPolling] = useState(false);
+  const [pollingError, setPollingError] = useState<string | null>(null);
+
+  async function fetchWorkflowCode() {
+    try {
+      setIsFetching(true);
+      const response = await fetch(API_PATH);
+      const data = await response.json();
+
+      if (!response.ok) {
+        throw new Error(data?.detail ?? "Unknown error");
+      }
+
+      setWorkflowFile(data);
+      setFetchingError(null);
+    } catch (error) {
+      const errorMessage =
+        error instanceof Error ? error.message : "Unknown error";
+      setFetchingError(errorMessage);
+      console.warn("Error fetching workflow code:", error);
+    } finally {
+      setIsFetching(false);
+    }
+  }
+
+  async function restartingWorkflow() {
+    if (!workflowFile) return;
+
+    const initialLastModified = workflowFile.last_modified;
+    setIsPolling(true);
+    setPollingError(null);
+
+    const pollStartTime = Date.now();
+
+    // interval refetching the updated workflow code
+    const poll = async () => {
+      if (Date.now() - pollStartTime > POLLING_TIMEOUT) {
+        setPollingError(
+          `Server not responding after ${POLLING_TIMEOUT / 1000} seconds.`,
+        );
+        return;
+      }
+
+      try {
+        const pollResponse = await fetch(API_PATH);
+        const pollData = (await pollResponse.json()) as WorkflowFile;
+        if (pollData.last_modified !== initialLastModified) {
+          setWorkflowFile(pollData);
+          setUpdatedCode(pollData.content);
+          setIsPolling(false);
+          setPollingError(null);
+          setDevModeOpen(false);
+        } else {
+          setTimeout(poll, 2000);
+        }
+      } catch (error) {
+        console.info("Polling error", error);
+        setTimeout(poll, 2000);
+      }
+    };
+
+    setTimeout(poll, 2000);
+  }
+
+  const handleResetCode = () => {
+    setUpdatedCode(workflowFile?.content ?? null);
+    setSaveError(null);
+  };
+
+  const handleSaveCode = async () => {
+    if (!workflowFile) return;
+
+    try {
+      setIsSaving(true);
+      const response = await fetch(API_PATH, {
+        method: "PUT",
+        headers: {
+          Accept: "application/json",
+          "Content-Type": "application/json",
+        },
+        body: JSON.stringify({
+          content: updatedCode,
+          file_path: workflowFile.file_path,
+        }),
+      });
+      const data = await response.json();
+      if (!response.ok) {
+        throw new Error(data?.detail ?? "Unknown error");
+      }
+      setSaveError(null);
+      await restartingWorkflow();
+    } catch (error) {
+      console.warn("Error saving workflow code:", error);
+      setSaveError(
+        error instanceof Error
+          ? error.message
+          : "Unknown error happened when saving workflow code",
+      );
+    } finally {
+      setIsSaving(false);
+    }
+  };
+
+  useEffect(() => {
+    if (devModeOpen) {
+      fetchWorkflowCode();
+    }
+  }, [devModeOpen]);
+
+  const codeEditorLanguage = fileExtensionToEditorLang(
+    workflowFile?.file_path.split(".").pop() ?? "",
+  );
+
+  return (
+    <>
+      <Button
+        onClick={() => setDevModeOpen(!devModeOpen)}
+        className="fixed right-2 top-1/2 origin-right -translate-y-1/2 rotate-90 transform rounded-l-md shadow-md transition-transform hover:-translate-x-1"
+      >
+        Dev Mode
+      </Button>
+
+      {isPolling && (
+        <div className="fixed inset-0 z-50 flex flex-col items-center justify-center bg-black/50 backdrop-blur-sm">
+          {!pollingError && (
+            <>
+              <Loader2 className="mb-4 h-16 w-16 animate-spin text-white" />
+              <p className="text-lg font-semibold text-white">
+                Applying changes and restarting server...
+              </p>
+              <p className="mt-2 text-sm text-slate-300">
+                Please wait for a while then you can start chatting with the
+                updated workflow.
+              </p>
+            </>
+          )}
+          {pollingError && (
+            <div className="bg-destructive/20 text-destructive-foreground mt-4 max-w-md rounded-md p-4 text-center">
+              <div className="mb-2 flex items-center justify-center gap-2">
+                <AlertCircle className="shrink-0" size={16} />
+                <h6 className="text-sm font-medium">Server Starting Error</h6>
+              </div>
+              <p className="text-sm">{pollingError}</p>
+
+              <p className="text-sm">
+                Please reload the page and check server logs.
+              </p>
+            </div>
+          )}
+        </div>
+      )}
+
+      <div
+        className={`border-border fixed right-0 top-0 z-10 h-full w-full border-l shadow-xl transition-all duration-300 ease-in-out ${
+          devModeOpen ? "translate-x-0 bg-black/50" : "translate-x-full"
+        }`}
+        onClick={() => setDevModeOpen(false)}
+      >
+        <div
+          className={`bg-background ml-auto flex h-full w-[800px] flex-col p-4`}
+          onClick={(e) => e.stopPropagation()}
+        >
+          <div className="mb-4 flex items-center justify-between">
+            <div>
+              <h2 className="text-xl font-bold">Workflow Editor</h2>
+              <p className="text-muted-foreground text-sm">
+                {isFetching ? (
+                  "Loading..."
+                ) : workflowFile ? (
+                  <>
+                    Edit the code of <b>{workflowFile.file_path}</b> and save to
+                    apply changes to your workflow.
+                  </>
+                ) : (
+                  ""
+                )}
+              </p>
+            </div>
+            <Button
+              variant="outline"
+              size="sm"
+              onClick={() => setDevModeOpen(false)}
+            >
+              Close
+            </Button>
+          </div>
+          <div className="flex-1 overflow-auto">
+            {fetchingError ? (
+              <div className="bg-destructive/10 text-destructive/70 mb-4 flex items-center gap-2 rounded-md p-4">
+                <AlertCircle className="shrink-0" size={16} />
+                <p className="text-sm font-medium">{fetchingError}</p>
+              </div>
+            ) : (
+              <CodeEditor
+                code={updatedCode ?? workflowFile?.content ?? ""}
+                onChange={setUpdatedCode}
+                language={codeEditorLanguage}
+              />
+            )}
+          </div>
+          <div className="mt-4 flex flex-col">
+            {saveError && (
+              <div className="bg-destructive/10 text-destructive/70 mb-4 rounded-md p-4">
+                <div className="mb-2 flex items-center gap-2">
+                  <AlertCircle className="shrink-0" size={16} />
+                  <h6 className="text-sm font-medium">Error Saving Code</h6>
+                </div>
+                <p className="whitespace-pre-wrap text-sm">{saveError}</p>
+              </div>
+            )}
+
+            <div className="flex justify-end gap-2">
+              <Button
+                variant="outline"
+                className="mr-2"
+                onClick={handleResetCode}
+              >
+                Reset Code
+              </Button>
+              <Button
+                onClick={handleSaveCode}
+                disabled={isSaving || !updatedCode || !workflowFile}
+              >
+                Save & Restart Server
+                {isSaving && <Loader2 className="ml-2 h-4 w-4 animate-spin" />}
+              </Button>
+            </div>
+          </div>
+        </div>
+      </div>
+    </>
+  );
+}

packages/server/package.json

@@ -1,7 +1,7 @@
 {
   "name": "@llamaindex/server",
   "description": "LlamaIndex Server",
-  "version": "0.2.0",
+  "version": "0.2.1",
   "type": "module",
   "main": "./dist/index.cjs",
   "module": "./dist/index.js",
@@ -55,7 +55,7 @@
     "@babel/traverse": "^7.27.0",
     "@babel/types": "^7.27.0",
     "@hookform/resolvers": "^5.0.1",
-    "@llamaindex/chat-ui": "0.4.3",
+    "@llamaindex/chat-ui": "0.4.4",
     "@radix-ui/react-accordion": "^1.2.3",
     "@radix-ui/react-alert-dialog": "^1.1.7",
     "@radix-ui/react-aspect-ratio": "^1.1.3",

packages/server/src/handlers/files.ts

@@ -1,7 +1,9 @@
+import { exec } from "child_process";
 import fs from "fs";
 import type { IncomingMessage, ServerResponse } from "http";
+import path from "path";
 import { promisify } from "util";
-import { sendJSONResponse } from "../utils/request";
+import { parseRequestBody, sendJSONResponse } from "../utils/request";
 
 export const handleServeFiles = async (
   req: IncomingMessage,
@@ -21,3 +23,84 @@ export const handleServeFiles = async (
     return sendJSONResponse(res, 404, { error: "File not found" });
   }
 };
+
+const DEFAULT_WORKFLOW_FILE_PATH = "src/app/workflow.ts"; // TODO: we can make it as a parameter in server later
+
+export const getWorkflowFile = async (
+  req: IncomingMessage,
+  res: ServerResponse,
+  filePath: string = DEFAULT_WORKFLOW_FILE_PATH,
+) => {
+  const fileExists = await promisify(fs.exists)(filePath);
+  if (!fileExists) {
+    return sendJSONResponse(res, 404, {
+      detail: `Dev mode is currently in beta. It only supports updating workflow file at ${DEFAULT_WORKFLOW_FILE_PATH}`,
+    });
+  }
+
+  const content = await promisify(fs.readFile)(filePath, "utf-8");
+  const last_modified = fs.statSync(filePath).mtime.getTime();
+  sendJSONResponse(res, 200, { content, file_path: filePath, last_modified });
+};
+
+export const updateWorkflowFile = async (
+  req: IncomingMessage,
+  res: ServerResponse,
+  filePath: string = DEFAULT_WORKFLOW_FILE_PATH,
+) => {
+  const body = await parseRequestBody(req);
+  const { content } = body as { content: string };
+
+  const fileExists = await promisify(fs.exists)(filePath);
+  if (!fileExists) {
+    return sendJSONResponse(res, 404, {
+      detail: `Dev mode is currently in beta. It only supports updating workflow file at ${DEFAULT_WORKFLOW_FILE_PATH}`,
+    });
+  }
+
+  try {
+    const resolvedFilePath = path.resolve(DEFAULT_WORKFLOW_FILE_PATH);
+    const result = await validateTypeScriptFile(resolvedFilePath, content);
+
+    if (!result.isValid) {
+      return sendJSONResponse(res, 400, {
+        detail: result.errors.join("\n"),
+      });
+    }
+
+    await promisify(fs.writeFile)(filePath, content);
+    sendJSONResponse(res, 200, { content });
+  } catch (error) {
+    console.error("Error updating workflow file:", error);
+    sendJSONResponse(res, 500, { error: "Failed to update workflow file" });
+  }
+};
+
+// use typescript package to validate the file syntax and imports
+async function validateTypeScriptFile(filePath: string, content: string) {
+  // Update workflow file directly will cause the server restart immediately.
+  // So we create a temporary file with the same content in the same directory as the workflow file
+  // This file will be used to validate the file syntax and imports. It will be deleted after validation.
+  const tempFilePath = path.join(
+    path.dirname(filePath),
+    `workflow_${Date.now()}.ts`,
+  );
+  fs.writeFileSync(tempFilePath, content);
+
+  const errors = [];
+  try {
+    const tscCommand = `npx tsc ${tempFilePath} --noEmit --skipLibCheck true`;
+    await promisify(exec)(tscCommand);
+  } catch (error) {
+    const errorMessage = (error as { stdout: string })?.stdout;
+    errors.push(errorMessage);
+  } finally {
+    // Clean up temporary file
+    if (fs.existsSync(tempFilePath)) fs.unlinkSync(tempFilePath);
+  }
+
+  return {
+    isValid: errors.length === 0,
+    errors: errors,
+  };
+}

packages/server/src/server.ts

@@ -9,8 +9,13 @@ import { promisify } from "util";
 import { handleChat } from "./handlers/chat";
 import { getLlamaCloudConfig } from "./handlers/cloud";
 import { getComponents } from "./handlers/components";
-import { handleServeFiles } from "./handlers/files";
+import {
+  getWorkflowFile,
+  handleServeFiles,
+  updateWorkflowFile,
+} from "./handlers/files";
 import type { LlamaIndexServerOptions } from "./types";
+
 const nextDir = path.join(__dirname, "..", "server");
 const configFile = path.join(__dirname, "..", "server", "public", "config.js");
 const dev = process.env.NODE_ENV !== "production";
@@ -44,6 +49,7 @@ export class LlamaIndexServer {
         ? "/api/chat/config/llamacloud"
         : undefined;
     const componentsApi = this.componentsDir ? "/api/components" : undefined;
+    const devMode = uiConfig?.devMode ?? false;
 
     // content in javascript format
     const content = `
@@ -52,7 +58,8 @@ export class LlamaIndexServer {
         APP_TITLE: ${JSON.stringify(appTitle)},
         LLAMA_CLOUD_API: ${JSON.stringify(llamaCloudApi)},
         STARTER_QUESTIONS: ${JSON.stringify(starterQuestions)},
-        COMPONENTS_API: ${JSON.stringify(componentsApi)}
+        COMPONENTS_API: ${JSON.stringify(componentsApi)},
+        DEV_MODE: ${JSON.stringify(devMode)}
       }
     `;
     fs.writeFileSync(configFile, content);
@@ -96,6 +103,14 @@ export class LlamaIndexServer {
         return getLlamaCloudConfig(req, res);
       }
 
+      if (pathname === "/api/dev/files/workflow" && req.method === "GET") {
+        return getWorkflowFile(req, res);
+      }
+
+      if (pathname === "/api/dev/files/workflow" && req.method === "PUT") {
+        return updateWorkflowFile(req, res);
+      }
+
       const handle = this.app.getRequestHandler();
       handle(req, res, parsedUrl);
     });

packages/server/src/types.ts

@@ -17,6 +17,7 @@ export type UIConfig = {
   starterQuestions?: string[];
   componentsDir?: string;
   llamaCloudIndexSelector?: boolean;
+  devMode?: boolean;
 };
 
 export type LlamaIndexServerOptions = NextAppOptions & {

pnpm-lock.yaml

@@ -181,8 +181,8 @@ importers:
         specifier: ^5.0.1
         version: 5.0.1(react-hook-form@7.56.1(react@19.1.0))
       '@llamaindex/chat-ui':
-        specifier: 0.4.3
-        version: 0.4.3(@babel/runtime@7.27.0)(@codemirror/autocomplete@6.18.6)(@codemirror/language@6.11.0)(@codemirror/lint@6.8.5)(@codemirror/search@6.5.10)(@codemirror/state@6.5.2)(@codemirror/theme-one-dark@6.1.2)(@codemirror/view@6.36.7)(@types/react-dom@19.1.2(@types/react@19.1.2))(@types/react@19.1.2)(codemirror@6.0.1)(react-dom@19.1.0(react@19.1.0))(react@19.1.0)
+        specifier: 0.4.4
+        version: 0.4.4(@babel/runtime@7.27.0)(@codemirror/autocomplete@6.18.6)(@codemirror/language@6.11.0)(@codemirror/lint@6.8.5)(@codemirror/search@6.5.10)(@codemirror/state@6.5.2)(@codemirror/theme-one-dark@6.1.2)(@codemirror/view@6.36.7)(@types/react-dom@19.1.2(@types/react@19.1.2))(@types/react@19.1.2)(codemirror@6.0.1)(react-dom@19.1.0(react@19.1.0))(react@19.1.0)
       '@llamaindex/env':
         specifier: ^0.1.29
         version: 0.1.29
@@ -392,6 +392,9 @@ importers:
       '@types/node':
         specifier: ^20.10.3
         version: 20.17.30
+      nodemon:
+        specifier: ^3.1.10
+        version: 3.1.10
       tsx:
         specifier: ^4.7.2
         version: 4.19.3
@@ -1177,8 +1180,8 @@ packages:
       zod:
         optional: true
 
-  '@llamaindex/chat-ui@0.4.3':
-    resolution: {integrity: sha512-JeS5pzEXZRRzTL70lHRtbWbaPjeZuMMHlqkTNBgYqc2eMM+o9VMOzVKKsXoYfOeE+wunqJd+cBrtkECGEmhRZg==}
+  '@llamaindex/chat-ui@0.4.4':
+    resolution: {integrity: sha512-sE3mJxlmAV3eiIaqOnioUNYYBLJJL8sy2mdFP4xXDf3PfkcEn0wT2Om/ButpVgIXHlPG9lONtv8mzw7hWq2Atg==}
     peerDependencies:
       react: ^18.2.0 || ^19.0.0 || ^19.0.0-rc
 
@@ -3882,6 +3885,10 @@ packages:
     resolution: {integrity: sha512-R3pbpkcIqv2Pm3dUwgjclDRVmWpTJW2DcMzcIhEXEx1oh/CEMObMm3KLmRJOdvhM7o4uQBnwr8pzRK2sJWIqfg==}
     engines: {node: '>= 0.4'}
 
+  has-flag@3.0.0:
+    resolution: {integrity: sha512-sKJf1+ceQBr4SMkvQnBDNDtf4TXpVhVGateu0t918bl30FnbE2m4vNLX+VWe/dpjlb+HugGYzW7uQXH98HPEYw==}
+    engines: {node: '>=4'}
+
   has-flag@4.0.0:
     resolution: {integrity: sha512-EykJT/Q1KjTWctppgIAgfSO0tKVuZUjhgMr17kqTumMl6Afv3EISleU7qZUzoXDFTAHTDC4NOoG/ZxU3EvlMPQ==}
     engines: {node: '>=8'}
@@ -3987,6 +3994,9 @@ packages:
   ieee754@1.2.1:
     resolution: {integrity: sha512-dcyqhDvX1C46lXZcVqCpK+FtMRQVdIMN6/Df5js2zouUsqG7I6sFxitIC+7KYK29KdXOLHdu9zL4sFnoVQnqaA==}
 
+  ignore-by-default@1.0.1:
+    resolution: {integrity: sha512-Ius2VYcGNk7T90CppJqcIkS5ooHUZyIQK+ClZfMfMNFEF9VSE73Fq+906u/CWu92x4gzZMWOwfFYckPObzdEbA==}
+
   ignore@5.3.2:
     resolution: {integrity: sha512-hsBTNUqQTDwkWtcdYI2i06Y/nUBEsNEDJKjWdigLvegy8kDuJAS8uRlpkkcQpyEXL0Z/pjDy5HBmMjRCJ2gq+g==}
     engines: {node: '>= 4'}
@@ -4805,6 +4815,11 @@ packages:
     resolution: {integrity: sha512-LA4ZjwlnUblHVgq0oBF3Jl/6h/Nvs5fzBLwdEF4nuxnFdsfajde4WfxtJr3CaiH+F6ewcIB/q4jQ4UzPyid+CQ==}
     hasBin: true
 
+  nodemon@3.1.10:
+    resolution: {integrity: sha512-WDjw3pJ0/0jMFmyNDp3gvY2YizjLmmOUQo6DEBY+JgdvW/yQ9mEeSw6H5ythl5Ny2ytb7f9C2nIbjSxMNzbJXw==}
+    engines: {node: '>=10'}
+    hasBin: true
+
   nopt@5.0.0:
     resolution: {integrity: sha512-Tbj67rffqceeLpcRXrT7vKAN8CwfPeIBgM7E6iBkmKLV7bEMwpGgYLGv0jACUsECaa/vuxP0IjEont6umdMgtQ==}
     engines: {node: '>=6'}
@@ -5258,6 +5273,9 @@ packages:
   proxy-from-env@1.1.0:
     resolution: {integrity: sha512-D+zkORCbA9f1tdWRK0RaCR3GPv50cMxcrz4X8k5LTSUD1Dkw47mKJEZQNunItRTkWwgtaUSo1RVFRIG9ZXiFYg==}
 
+  pstree.remy@1.1.8:
+    resolution: {integrity: sha512-77DZwxQmxKnu3aR542U+X8FypNzbfJ+C5XQDk3uWjWxn6151aIMGthWYRXTqT1E5oJvg+ljaa2OJi+VfvCOQ8w==}
+
   pump@3.0.2:
     resolution: {integrity: sha512-tUPXtzlGM8FE3P0ZL6DVs/3P58k9nk8/jZeQCurTJylQA8qFYzHFfhBJkuqyE0FifOsQ0uKWekiZ5g8wtr28cw==}
 
@@ -5674,6 +5692,10 @@ packages:
   simple-swizzle@0.2.2:
     resolution: {integrity: sha512-JA//kQgZtbuY83m+xT+tXJkmJncGMTFT+C+g2h2R9uxkYIrE2yy9sgmcLhCnw57/WSD+Eh3J97FPEDFnbXnDUg==}
 
+  simple-update-notifier@2.0.0:
+    resolution: {integrity: sha512-a2B9Y0KlNXl9u/vsW6sTIu9vGEpfKu2wRV6l1H3XEas/0gUIzGzBoP/IouTcUQbm9JWZLH3COxyn03TYlFax6w==}
+    engines: {node: '>=10'}
+
   sisteransi@1.0.5:
     resolution: {integrity: sha512-bLGGlR1QxBcynn2d5YmDX4MGjlZvy2MRBDRNHLJ8VI6l6+9FUiyTFNJ0IveOSP0bcXgVDPRcfGqA0pjaqUpfVg==}
 
@@ -5832,6 +5854,10 @@ packages:
       babel-plugin-macros:
         optional: true
 
+  supports-color@5.5.0:
+    resolution: {integrity: sha512-QjVjwdXIt408MIiAqCX4oUKsgU2EqAGzs2Ppkm4aQYbjm+ZEWEcW4SfFNTr4uMNZma0ey4f5lgLrkB0aX0QMow==}
+    engines: {node: '>=4'}
+
   supports-color@7.2.0:
     resolution: {integrity: sha512-qpCAvRl9stuOHveKsn7HncJRvv501qIacKzQlO/+Lwxc9+0q2wLyv4Dfvt80/DPn2pqOBsJdDiogXGR9+OvwRw==}
     engines: {node: '>=8'}
@@ -5928,6 +5954,10 @@ packages:
   to-vfile@6.1.0:
     resolution: {integrity: sha512-BxX8EkCxOAZe+D/ToHdDsJcVI4HqQfmw0tCkp31zf3dNP/XWIAjU4CmeuSwsSoOzOTqHPOL0KUzyZqJplkD0Qw==}
 
+  touch@3.1.1:
+    resolution: {integrity: sha512-r0eojU4bI8MnHr8c5bNo7lJDdI2qXlWWJk6a9EAFG7vbhTjElYhBVS3/miuE0uOuoLdb8Mc/rVfsmm6eo5o9GA==}
+    hasBin: true
+
   tr46@0.0.3:
     resolution: {integrity: sha512-N3WMsuqV66lT30CrXNbEjx4GEwlow3v6rr4mCcv6prnfwhS01rkgyFdjPNBYd9br7LpXV1+Emh01fHnq2Gdgrw==}
 
@@ -6018,6 +6048,9 @@ packages:
     resolution: {integrity: sha512-nWJ91DjeOkej/TA8pXQ3myruKpKEYgqvpw9lz4OPHj/NWFNluYrjbz9j01CJ8yKQd2g4jFoOkINCTW2I5LEEyw==}
     engines: {node: '>= 0.4'}
 
+  undefsafe@2.0.5:
+    resolution: {integrity: sha512-WxONCrssBM8TSPRqN5EmsjVrsv4A8X12J4ArBiiayv3DyyG3ZlIg6yysuuSYdZsVz3TKcTg2fd//Ujd4CHV1iA==}
+
   underscore@1.13.7:
     resolution: {integrity: sha512-GMXzWtsc57XAtguZgaQViUOzs0KTkk8ojr3/xAxXLITqf/3EMwxC0inyETfDFjH/Krbhuep0HNbbjI9i/q3F3g==}
 
@@ -6462,7 +6495,7 @@ snapshots:
       '@babel/parser': 7.27.0
       '@babel/template': 7.27.0
       '@babel/types': 7.27.0
-      debug: 4.4.0
+      debug: 4.4.0(supports-color@5.5.0)
       globals: 11.12.0
     transitivePeerDependencies:
       - supports-color
@@ -6891,7 +6924,7 @@ snapshots:
   '@eslint/config-array@0.19.2':
     dependencies:
       '@eslint/object-schema': 2.1.6
-      debug: 4.4.0
+      debug: 4.4.0(supports-color@5.5.0)
       minimatch: 3.1.2
     transitivePeerDependencies:
       - supports-color
@@ -6909,7 +6942,7 @@ snapshots:
   '@eslint/eslintrc@3.3.1':
     dependencies:
       ajv: 6.12.6
-      debug: 4.4.0
+      debug: 4.4.0(supports-color@5.5.0)
       espree: 10.3.0
       globals: 14.0.0
       ignore: 5.3.2
@@ -7113,7 +7146,7 @@ snapshots:
       next: 15.3.1(@opentelemetry/api@1.9.0)(@playwright/test@1.52.0)(react-dom@19.1.0(react@19.1.0))(react@19.1.0)
       zod: 3.24.3
 
-  '@llamaindex/chat-ui@0.4.3(@babel/runtime@7.27.0)(@codemirror/autocomplete@6.18.6)(@codemirror/language@6.11.0)(@codemirror/lint@6.8.5)(@codemirror/search@6.5.10)(@codemirror/state@6.5.2)(@codemirror/theme-one-dark@6.1.2)(@codemirror/view@6.36.7)(@types/react-dom@19.1.2(@types/react@19.1.2))(@types/react@19.1.2)(codemirror@6.0.1)(react-dom@19.1.0(react@19.1.0))(react@19.1.0)':
+  '@llamaindex/chat-ui@0.4.4(@babel/runtime@7.27.0)(@codemirror/autocomplete@6.18.6)(@codemirror/language@6.11.0)(@codemirror/lint@6.8.5)(@codemirror/search@6.5.10)(@codemirror/state@6.5.2)(@codemirror/theme-one-dark@6.1.2)(@codemirror/view@6.36.7)(@types/react-dom@19.1.2(@types/react@19.1.2))(@types/react@19.1.2)(codemirror@6.0.1)(react-dom@19.1.0(react@19.1.0))(react@19.1.0)':
     dependencies:
       '@codemirror/lang-css': 6.3.1
       '@codemirror/lang-html': 6.4.9
@@ -8531,7 +8564,7 @@ snapshots:
       '@typescript-eslint/types': 8.31.0
       '@typescript-eslint/typescript-estree': 8.31.0(typescript@5.8.3)
       '@typescript-eslint/visitor-keys': 8.31.0
-      debug: 4.4.0
+      debug: 4.4.0(supports-color@5.5.0)
       eslint: 9.22.0(jiti@2.4.2)
       typescript: 5.8.3
     transitivePeerDependencies:
@@ -8546,7 +8579,7 @@ snapshots:
     dependencies:
       '@typescript-eslint/typescript-estree': 8.31.0(typescript@5.8.3)
       '@typescript-eslint/utils': 8.31.0(eslint@9.22.0(jiti@2.4.2))(typescript@5.8.3)
-      debug: 4.4.0
+      debug: 4.4.0(supports-color@5.5.0)
       eslint: 9.22.0(jiti@2.4.2)
       ts-api-utils: 2.1.0(typescript@5.8.3)
       typescript: 5.8.3
@@ -8559,7 +8592,7 @@ snapshots:
     dependencies:
       '@typescript-eslint/types': 8.31.0
       '@typescript-eslint/visitor-keys': 8.31.0
-      debug: 4.4.0
+      debug: 4.4.0(supports-color@5.5.0)
       fast-glob: 3.3.3
       is-glob: 4.0.3
       minimatch: 9.0.5
@@ -8743,7 +8776,7 @@ snapshots:
 
   agent-base@6.0.2:
     dependencies:
-      debug: 4.4.0
+      debug: 4.4.0(supports-color@5.5.0)
     transitivePeerDependencies:
       - supports-color
     optional: true
@@ -9101,7 +9134,7 @@ snapshots:
       normalize-path: 3.0.0
       readdirp: 3.6.0
     optionalDependencies:
-      fsevents: 2.3.2
+      fsevents: 2.3.3
 
   chownr@1.1.4:
     optional: true
@@ -9297,9 +9330,11 @@ snapshots:
     dependencies:
       ms: 2.1.3
 
-  debug@4.4.0:
+  debug@4.4.0(supports-color@5.5.0):
     dependencies:
       ms: 2.1.3
+    optionalDependencies:
+      supports-color: 5.5.0
 
   decimal.js-light@2.5.1: {}
 
@@ -9665,7 +9700,7 @@ snapshots:
   eslint-import-resolver-typescript@3.10.1(eslint-plugin-import@2.31.0)(eslint@9.22.0(jiti@2.4.2)):
     dependencies:
       '@nolyfill/is-core-module': 1.0.39
-      debug: 4.4.0
+      debug: 4.4.0(supports-color@5.5.0)
       eslint: 9.22.0(jiti@2.4.2)
       get-tsconfig: 4.10.0
       is-bun-module: 2.0.0
@@ -9789,7 +9824,7 @@ snapshots:
       ajv: 6.12.6
       chalk: 4.1.2
       cross-spawn: 7.0.6
-      debug: 4.4.0
+      debug: 4.4.0(supports-color@5.5.0)
       escape-string-regexp: 4.0.0
       eslint-scope: 8.3.0
       eslint-visitor-keys: 4.2.0
@@ -10168,6 +10203,8 @@ snapshots:
 
   has-bigints@1.1.0: {}
 
+  has-flag@3.0.0: {}
+
   has-flag@4.0.0: {}
 
   has-property-descriptors@1.0.2:
@@ -10278,7 +10315,7 @@ snapshots:
   https-proxy-agent@5.0.1:
     dependencies:
       agent-base: 6.0.2
-      debug: 4.4.0
+      debug: 4.4.0(supports-color@5.5.0)
     transitivePeerDependencies:
       - supports-color
     optional: true
@@ -10304,6 +10341,8 @@ snapshots:
   ieee754@1.2.1:
     optional: true
 
+  ignore-by-default@1.0.1: {}
+
   ignore@5.3.2: {}
 
   immediate@3.0.6: {}
@@ -10664,7 +10703,7 @@ snapshots:
     dependencies:
       chalk: 5.4.1
       commander: 13.1.0
-      debug: 4.4.0
+      debug: 4.4.0(supports-color@5.5.0)
       execa: 8.0.1
       lilconfig: 3.1.3
       listr2: 8.3.2
@@ -11115,7 +11154,7 @@ snapshots:
   micromark@3.2.0:
     dependencies:
       '@types/debug': 4.1.12
-      debug: 4.4.0
+      debug: 4.4.0(supports-color@5.5.0)
       decode-named-character-reference: 1.1.0
       micromark-core-commonmark: 1.1.0
       micromark-factory-space: 1.1.0
@@ -11260,6 +11299,19 @@ snapshots:
 
   node-gyp-build@4.8.4: {}
 
+  nodemon@3.1.10:
+    dependencies:
+      chokidar: 3.6.0
+      debug: 4.4.0(supports-color@5.5.0)
+      ignore-by-default: 1.0.1
+      minimatch: 3.1.2
+      pstree.remy: 1.1.8
+      semver: 7.7.1
+      simple-update-notifier: 2.0.0
+      supports-color: 5.5.0
+      touch: 3.1.1
+      undefsafe: 2.0.5
+
   nopt@5.0.0:
     dependencies:
       abbrev: 1.1.1
@@ -11672,6 +11724,8 @@ snapshots:
 
   proxy-from-env@1.1.0: {}
 
+  pstree.remy@1.1.8: {}
+
   pump@3.0.2:
     dependencies:
       end-of-stream: 1.4.4
@@ -12235,6 +12289,10 @@ snapshots:
       is-arrayish: 0.3.2
     optional: true
 
+  simple-update-notifier@2.0.0:
+    dependencies:
+      semver: 7.7.1
+
   sisteransi@1.0.5: {}
 
   slash@3.0.0: {}
@@ -12393,6 +12451,10 @@ snapshots:
       client-only: 0.0.1
       react: 19.1.0
 
+  supports-color@5.5.0:
+    dependencies:
+      has-flag: 3.0.0
+
   supports-color@7.2.0:
     dependencies:
       has-flag: 4.0.0
@@ -12489,6 +12551,8 @@ snapshots:
       is-buffer: 2.0.5
       vfile: 4.2.1
 
+  touch@3.1.1: {}
+
   tr46@0.0.3: {}
 
   tree-sitter@0.22.4:
@@ -12593,6 +12657,8 @@ snapshots:
       has-symbols: 1.1.0
       which-boxed-primitive: 1.1.1
 
+  undefsafe@2.0.5: {}
+
   underscore@1.13.7: {}
 
   undici-types@5.26.5: {}
@@ -12820,7 +12886,7 @@ snapshots:
   vite-node@2.1.9(@types/node@20.17.30)(lightningcss@1.29.2):
     dependencies:
       cac: 6.7.14
-      debug: 4.4.0
+      debug: 4.4.0(supports-color@5.5.0)
       es-module-lexer: 1.7.0
       pathe: 1.1.2
       vite: 5.4.18(@types/node@20.17.30)(lightningcss@1.29.2)
@@ -12855,7 +12921,7 @@ snapshots:
       '@vitest/spy': 2.1.9
       '@vitest/utils': 2.1.9
       chai: 5.2.0
-      debug: 4.4.0
+      debug: 4.4.0(supports-color@5.5.0)
       expect-type: 1.2.1
       magic-string: 0.30.17
       pathe: 1.1.2
@@ -12886,7 +12952,7 @@ snapshots:
     dependencies:
       chalk: 4.1.2
       commander: 9.5.0
-      debug: 4.4.0
+      debug: 4.4.0(supports-color@5.5.0)
     transitivePeerDependencies:
       - supports-color
 

python/llama-index-server/README.md

@@ -72,7 +72,7 @@ app = LlamaIndexServer(
 
 The LlamaIndexServer accepts the following configuration parameters:
 
-- `workflow_factory`: A callable that creates a workflow instance for each request
+- `workflow_factory`: A callable that creates a workflow instance for each request. See [Workflow factory contract](#workflow-factory-contract) for more details.
 - `logger`: Optional logger instance (defaults to uvicorn logger)
 - `use_default_routers`: Whether to include default routers (chat, static file serving)
 - `env`: Environment setting ('dev' enables CORS and UI by default)
@@ -83,10 +83,36 @@ The LlamaIndexServer accepts the following configuration parameters:
   - `ui_path`: Path for downloaded UI static files (default: ".ui")
   - `component_dir`: The directory for custom UI components rendering events emitted by the workflow. The default is None, which does not render custom UI components.
   - `llamacloud_index_selector`: Whether to show the LlamaCloud index selector in the chat UI (default: False). Requires `LLAMA_CLOUD_API_KEY` to be set.
+  - `dev_mode`: When enabled, you can update workflow code in the UI and see the changes immediately. It's currently in beta and only supports updating workflow code at `app/workflow.py`. You might also need to set `env="dev"` and start the server with the reload feature enabled.
 - `verbose`: Enable verbose logging
 - `api_prefix`: API route prefix (default: "/api")
 - `server_url`: The deployment URL of the server (default is None)
 
+## Workflow factory contract
+
+The `workflow_factory` provided will be called for each chat request to initialize a new workflow instance. Additionally, we provide the [ChatRequest](https://github.com/run-llama/create-llama/blob/afe9e9fc16427d20e1dfb635a45e7ed4b46285cb/python/llama-index-server/llama_index/server/api/models.py#L32) object, which includes the request information that is helpful for initializing the workflow. For example:
+```python
+def create_workflow(chat_request: ChatRequest) -> Workflow:
+    # using messages from the chat request to initialize the workflow
+    return MyCustomWorkflow(chat_request.messages)
+```
+
+Your workflow will be executed once for each chat request with the following input parameters are included in workflow's `StartEvent`:
+- `user_msg` [str]: The current user message
+- `chat_history` [list[[ChatMessage](https://docs.llamaindex.ai/en/stable/api_reference/prompts/#llama_index.core.prompts.ChatMessage)]]: All the previous messages of the conversation
+
+Example:
+```python
+@step
+def handle_start_event(ev: StartEvent) -> MyNextEvent:
+    user_msg = ev.user_msg
+    chat_history = ev.chat_history
+    ...
+```
+
+Your workflows can emit `UIEvent` events to render [Custom UI Components](https://github.com/run-llama/create-llama/blob/main/python/llama-index-server/docs/custom_ui_component.md) in the chat UI to improve the user experience.
+Furthermore, you can send `ArtifactEvent` events to render code or document [Artifacts](https://github.com/run-llama/create-llama/blob/main/python/llama-index-server/docs/custom_artifact_event.md) in a dedicated Canvas panel in the chat UI.
+
 ## Default Routers and Features
 
 ### Chat Router
@@ -107,11 +133,6 @@ When enabled, the server provides a chat interface at the root path (`/`) with:
 - Real-time chat interface
 - API endpoint integration
 
-### Custom UI Components
-
-You can add custom UI components for your workflow by providing `component_dir` config and adding custom .jsx or .tsx files to the directory.
-See [Custom UI Components](https://github.com/run-llama/create-llama/blob/main/llama-index-server/docs/custom_ui_component.md) for more details.
-
 ## Development Mode
 
 In development mode (`env="dev"`), the server:
@@ -120,6 +141,20 @@ In development mode (`env="dev"`), the server:
 - Automatically includes the chat UI
 - Provides more verbose logging
 
+### Workflow Editor (Beta)
+
+In development mode, you can set `dev_mode` to `True` in the UI configuration to enable the workflow editor, which allows you to edit the workflow code directly in the browser.
+
+```python
+app = LlamaIndexServer(
+    workflow_factory=create_workflow,
+    env="dev",
+    ui_config={"dev_mode": True},
+)
+```
+
+**Note**: The workflow editor is currently in beta and only supports updating LlamaIndexServer projects created with [create-llama](https://github.com/run-llama/create-llama/). You also need to start the server via `fastapi dev` so that the server can hot reload the workflow code.
+
 ## API Endpoints
 
 The server provides the following default endpoints:
@@ -130,11 +165,10 @@ The server provides the following default endpoints:
 
 ## Best Practices
 
-1. Always provide a workflow factory that creates fresh workflow instances
-2. Use environment variables for sensitive configuration
-3. Enable verbose logging during development
-4. Configure CORS appropriately for your deployment environment
-5. Use starter questions to guide users in the chat UI
+1. Use environment variables for sensitive configuration
+2. Enable verbose logging during development
+3. Configure CORS appropriately for your deployment environment
+4. Use starter questions to guide users in the chat UI
 
 ## Getting Started with a New Project
 

python/llama-index-server/docs/custom_artifact_event.md

@@ -0,0 +1,59 @@
+# Sending Artifacts to the UI
+
+In addition to UI events for custom components, LlamaIndex Server supports a special `ArtifactEvent` to send structured data like generated documents or code snippets to the UI. These artifacts are displayed in a dedicated "Canvas" panel in the chat interface.
+
+## Artifact Event Structure
+
+To send an artifact, your workflow needs to emit an event with `type: "artifact"`. The `data` payload of this event should include:
+
+- `type`: An `ArtifactType` enum indicating the type of artifact (e.g., `ArtifactType.DOCUMENT`, `ArtifactType.CODE`).
+- `created_at`: A timestamp (e.g., `int(time.time())`) indicating when the artifact was created.
+- `data`: An object containing the specific details of the artifact. The structure of this object depends on the artifact `type`. For example, `DocumentArtifactData` or `CodeArtifactData`.
+
+## Defining and Sending an ArtifactEvent
+
+First, import the necessary classes:
+
+```python
+import time
+from llama_index.server.api.models import (
+    Artifact,
+    ArtifactEvent,
+    ArtifactType,
+    DocumentArtifactData,
+    # CodeArtifactData, # Import if sending code artifacts
+)
+```
+
+Then, within your workflow logic, use `ctx.write_event_to_stream` to emit the event. Here's an example of sending a document artifact, taken from [document_workflow.py](/python/llama-index-server/examples/artifact/document_workflow.py):
+
+```python
+# Assuming 'ctx' is the workflow Context and 'content' is a markdown string
+
+ctx.write_event_to_stream(
+    ArtifactEvent(
+        data=Artifact(
+            type=ArtifactType.DOCUMENT,
+            created_at=int(time.time()),
+            data=DocumentArtifactData(
+                title="My cooking recipes",
+                content=content,
+                type="markdown",
+            ),
+        ),
+    )
+)
+```
+
+This will send the artifact to the LlamaIndex Server UI, where it will be rendered in the Canvas panel by a renderer depending on the artifact type. For `ArtifactType.DOCUMENT`, this uses a `DocumentArtifactViewer`.
+
+## Available Artifact Types
+
+LlamaIndex Server currently supports the following artifact types:
+
+- `ArtifactType.DOCUMENT`: For text-based documents like Markdown or HTML.
+  - `data` should be an instance of `DocumentArtifactData` which includes `title: str`, `content: str`, and `type: Literal["markdown", "html"]`.
+- `ArtifactType.CODE`: For code snippets.
+  - `data` should be an instance of `CodeArtifactData` which includes `title: str`, `code: str`, and `language: str`.
+
+Ensure you provide the correct data model corresponding to the `ArtifactType` you are sending. You can find these data models in `llama_index.server.api.models`. 

python/llama-index-server/examples/simple-agent/README.md

@@ -0,0 +1,38 @@
+# A simple chat app
+
+This guide explains how to set up and use the LlamaIndex server with a simple chatbot agent.
+
+## Prerequisites
+
+- [uv](https://github.com/astral-sh/uv) installed (a fast Python package manager and runner)
+- An OpenAI API key
+
+## Steps
+
+1. **Set the OpenAI API Key**
+
+   Export your OpenAI API key as an environment variable:
+
+   ```sh
+   export OPENAI_API_KEY=your_openai_api_key_here
+   ```
+
+2. **Run the Server Using uv**
+
+   Start the server with the following command:
+
+   ```sh
+   uv run workflow.py
+   ```
+
+   This will launch the FastAPI server using the workflow defined in `main.py`.
+
+3. **Access the Application**
+
+   Open your browser and go to:
+
+   ```
+   http://localhost:8000
+   ```
+
+   You will see the LlamaIndex chat app UI, where you can interact with the agent.

python/llama-index-server/examples/simple-agent/app/workflow.py

@@ -0,0 +1,14 @@
+from typing import Optional
+
+from llama_index.core.agent.workflow import AgentWorkflow
+from llama_index.core.settings import Settings
+from llama_index.llms.openai import OpenAI
+from llama_index.server.api.models import ChatRequest
+
+
+def create_workflow(chat_request: Optional[ChatRequest] = None) -> AgentWorkflow:
+    return AgentWorkflow.from_tools_or_functions(
+        tools_or_functions=[],
+        llm=Settings.llm or OpenAI(model="gpt-4o-mini"),
+        system_prompt="You are a helpful assistant that can tell a joke about Llama.",
+    )

python/llama-index-server/examples/simple-agent/main.py

@@ -0,0 +1,29 @@
+from app.workflow import create_workflow
+from fastapi import FastAPI
+
+from llama_index.server import LlamaIndexServer, UIConfig
+
+
+def create_app() -> FastAPI:
+    app = LlamaIndexServer(
+        workflow_factory=create_workflow,
+        ui_config=UIConfig(
+            app_title="Artifact",
+            starter_questions=[
+                "Tell me a funny joke.",
+                "Tell me some jokes about AI.",
+            ],
+            component_dir="components",
+            dev_mode=True,  # To show the dev UI, should disable this in production
+        ),
+    )
+    return app
+
+
+app = create_app()
+
+
+if __name__ == "__main__":
+    import uvicorn
+
+    uvicorn.run("main:app", host="0.0.0.0", port=8000, reload=True)

python/llama-index-server/llama_index/server/api/routers/__init__.py

@@ -1,4 +1,9 @@
 from llama_index.server.api.routers.chat import chat_router
 from llama_index.server.api.routers.ui import custom_components_router
+from llama_index.server.api.routers.dev import dev_router
 
-__all__ = ["chat_router", "custom_components_router"]
+__all__ = [
+    "chat_router",
+    "custom_components_router",
+    "dev_router",
+]

python/llama-index-server/llama_index/server/api/routers/dev.py

@@ -0,0 +1,102 @@
+import os
+import tempfile
+
+from fastapi import APIRouter, HTTPException
+from pydantic import BaseModel, Field
+
+from llama_index.server.settings import server_settings
+from llama_index.server.utils.workflow_validation import validate_workflow_file
+
+
+class WorkflowFile(BaseModel):
+    last_modified: int
+    file_path: str = Field(
+        default="app/workflow.py",
+        description="Relative path to the workflow file",
+    )
+    content: str
+
+
+class WorkflowFileUpdate(BaseModel):
+    content: str
+    file_path: str = Field(
+        default="app/workflow.py",
+        description="Relative path to the workflow file",
+    )
+
+
+class WorkflowValidationResult(BaseModel):
+    valid: bool
+    error: str
+
+
+def dev_router() -> APIRouter:
+    # Use a prefix here to avoid conflicts with other routers
+    # but we probably don't need to do this
+    router = APIRouter(prefix="/dev", tags=["dev"])
+
+    default_workflow_file_path = "app/workflow.py"
+
+    @router.get("/files/workflow")
+    async def get_workflow_file() -> WorkflowFile:
+        """
+        Fetch the current workflow code
+        """
+        # Check if the file exists
+        if not os.path.exists(default_workflow_file_path):
+            raise HTTPException(
+                status_code=400,
+                detail="Dev mode is currently in beta. It only supports updating workflow file at 'app/workflow.py'",
+            )
+        stat = os.stat(default_workflow_file_path)
+        with open(default_workflow_file_path, "r") as f:
+            return WorkflowFile(
+                last_modified=int(stat.st_mtime),
+                file_path=default_workflow_file_path,
+                content=f.read(),
+            )
+
+    @router.post("/files/workflow/validate")
+    async def validate_workflow(file: WorkflowFileUpdate) -> WorkflowValidationResult:
+        """
+        Validate the current workflow code
+        """
+        try:
+            if file.file_path != default_workflow_file_path:
+                raise HTTPException(
+                    status_code=400, detail=f"Updating {file.file_path} is not allowed"
+                )
+            validate_workflow_file(
+                workflow_content=file.content,
+                factory_signature=server_settings.workflow_factory_signature,
+            )
+            return WorkflowValidationResult(valid=True, error="")
+        except Exception as e:
+            raise HTTPException(status_code=400, detail=str(e))
+
+    @router.put("/files/workflow")
+    async def put_workflow_file(update: WorkflowFileUpdate) -> None:
+        """
+        Update the current workflow code
+        """
+        # Validations
+        if update.file_path != default_workflow_file_path:
+            raise HTTPException(
+                status_code=400, detail=f"Updating {update.file_path} is not allowed"
+            )
+        with tempfile.NamedTemporaryFile("w", suffix=".py", delete=False) as tmp:
+            tmp.write(update.content)
+            tmp_path = tmp.name
+        try:
+            # Validate workflow file using the actual callable name from the workflow_factory
+            factory_func_name = server_settings.workflow_factory_signature
+            validate_workflow_file(
+                workflow_path=tmp_path, factory_signature=factory_func_name
+            )
+        except Exception as e:
+            raise HTTPException(status_code=400, detail=str(e))
+        # If all checks pass, overwrite the real file
+        with open(default_workflow_file_path, "w") as f:
+            f.write(update.content)
+
+    return router

python/llama-index-server/llama_index/server/server.py

@@ -10,7 +10,11 @@ from fastapi.staticfiles import StaticFiles
 from pydantic import BaseModel, Field
 
 from llama_index.core.workflow import Workflow
-from llama_index.server.api.routers import chat_router, custom_components_router
+from llama_index.server.api.routers import (
+    chat_router,
+    custom_components_router,
+    dev_router,
+)
 from llama_index.server.chat_ui import download_chat_ui
 from llama_index.server.settings import server_settings
 
@@ -33,6 +37,9 @@ class UIConfig(BaseModel):
     component_dir: Optional[str] = Field(
         default=None, description="The directory to custom UI components code"
     )
+    dev_mode: bool = Field(
+        default=False, description="Whether to enable the UI dev mode"
+    )
 
     def get_config_content(self) -> str:
         return json.dumps(
@@ -46,6 +53,7 @@ class UIConfig(BaseModel):
                 "COMPONENTS_API": f"{server_settings.api_url}/components"
                 if self.component_dir
                 else None,
+                "DEV_MODE": self.dev_mode,
             },
             indent=2,
         )
@@ -100,24 +108,33 @@ class LlamaIndexServer(FastAPI):
             server_settings.set_url(server_url)
         if api_prefix:
             server_settings.set_api_prefix(api_prefix)
-
-        if self.use_default_routers:
-            self.add_default_routers()
+        server_settings.set_workflow_factory(workflow_factory.__name__)
 
         if str(env).lower() == "dev":
             self.allow_cors("*")
             if self.ui_config.enabled is None:
                 self.ui_config.enabled = True
-
+        else:
+            if self.ui_config.enabled and self.ui_config.dev_mode:
+                raise ValueError(
+                    "UI dev mode requires the environment variable for LlamaIndexServer to be set to 'dev' and start the FastAPI app in dev mode."
+                )
         if self.ui_config.enabled is None:
             self.ui_config.enabled = False
 
+        # Routers
+        if self.use_default_routers:
+            self.add_default_routers()
+
+        # Should mount ui at the end
         if self.ui_config.enabled:
             self.mount_ui()
 
     # Default routers
     def add_default_routers(self) -> None:
         self.add_chat_router()
+        if self.ui_config.enabled and self.ui_config.dev_mode:
+            self.include_router(dev_router(), prefix=server_settings.api_prefix)
         self.mount_data_dir()
         self.mount_output_dir()
 

python/llama-index-server/llama_index/server/settings.py

@@ -11,6 +11,10 @@ class ServerSettings(BaseSettings):
         default="/api",
         description="The prefix for the API endpoints",
     )
+    workflow_factory_signature: str = Field(
+        default="",
+        description="The signature of the workflow factory function",
+    )
 
     @property
     def file_server_url_prefix(self) -> str:
@@ -40,6 +44,9 @@ class ServerSettings(BaseSettings):
         self.api_prefix = v
         self.validate_api_prefix(v)  # type: ignore
 
+    def set_workflow_factory(self, v: str) -> None:
+        self.workflow_factory_signature = v
+
     class Config:
         env_file_encoding = "utf-8"
 

python/llama-index-server/llama_index/server/utils/workflow_validation.py

@@ -0,0 +1,54 @@
+"""
+Utilities for validating workflow.py files (syntax and import checks only).
+"""
+
+import ast
+import importlib.util
+from typing import Optional
+
+
+def validate_workflow_file(
+    workflow_path: Optional[str] = None,
+    workflow_content: Optional[str] = None,
+    factory_signature: Optional[str] = None,
+) -> None:
+    """
+    Validate that the workflow file is syntactically correct, can be imported, and defines a callable factory function with the given name.
+    Raises an exception if invalid.
+    """
+    if workflow_path is None and workflow_content is None:
+        raise ValueError("Either workflow_path or workflow_content must be provided")
+
+    # 1. Syntax check
+    if workflow_path is not None:
+        with open(workflow_path, "r") as f:
+            content = f.read()
+    else:
+        if workflow_content is None:
+            raise ValueError(
+                "workflow_content must be provided if workflow_path is not specified"
+            )
+        content = workflow_content
+    try:
+        ast.parse(content)
+    except SyntaxError as e:
+        raise ValueError(f"Syntax error in workflow: {e}")
+
+    # 2. Import check (will catch missing modules, etc.)
+    spec = importlib.util.spec_from_file_location("workflow", workflow_path)
+    if spec is None or spec.loader is None:
+        raise ValueError(f"Could not load module specification for {workflow_path}")
+
+    mod = importlib.util.module_from_spec(spec)
+    try:
+        spec.loader.exec_module(mod)
+    except Exception as e:
+        raise ValueError(f"Import error: {e}")
+
+    # 3. Contract validation: require the given factory function name
+    if factory_signature:
+        if not hasattr(mod, factory_signature):
+            raise ValueError(f"Missing required function: '{factory_signature}'")
+        obj = getattr(mod, factory_signature)
+        if not callable(obj):
+            raise ValueError(f"'{factory_signature}' is not callable")