Connect Langflow to Lark (Feishu)

This recipe puts your Langflow app behind a Lark (Feishu) bot. LangBot receives messages from Lark (Feishu), runs them through a pipeline, and sends the answer back, so you do not write any platform code.

Langflow builds agents and flows with a drag-and-drop editor. LangBot runs a flow through the Langflow API for every message.

What you need

• A running LangBot instance: LangBot Cloud (no server needed) or a self-hosted deployment with Docker or uvx langbot.
• A Langflow account or instance that LangBot can reach over the network.
• A Feishu or Lark custom app (app_id and app_secret). The one-click setup in LangBot can create and authorize it for you.

Networking

The default WebSocket long connection needs no public IP. Where long connection is unavailable (for example some Lark international setups), webhook mode requires a public HTTPS address; LangBot Cloud includes one.

1. Prepare Langflow

1. Build a flow in Langflow (the Simple Agent template is a good start).
2. Create an API key under Settings.
3. Copy the Flow ID from Share → API access.

2. Create a pipeline

Open Pipelines in the LangBot WebUI, create a pipeline (or edit the default one) and set AI as follows. If the runner is not listed, install the official runner plugin from Plugins or the LangBot Space marketplace.

3. Create the Lark (Feishu) bot

1. Create a bot with the Lark adapter, select the platform domain (Feishu or Lark) and use One-Click Setup, or enter app_id and app_secret manually.
2. Add the message permissions and event subscriptions from the guide (and the card permissions if you want streaming cards), then publish an app version.

4. Bind and test

Open the bot, select the pipeline you created, save and make sure the bot is enabled.

Search for the bot in Feishu/Lark, send it a direct message, then add it to a group and mention it.

Troubleshooting

• Connection refused: http://localhost:7860 only works when Langflow runs on the same host and network namespace as LangBot.
• No messages arrive: confirm the app version is published and the event subscription uses the same mode (long connection or webhook) as LangBot.
• Check Monitoring in the WebUI: every message, pipeline run and error is recorded there.

FAQ

Do I need a server with a public IP for Lark (Feishu)?

Not necessarily. The default WebSocket long connection needs no public IP. Where long connection is unavailable (for example some Lark international setups), webhook mode requires a public HTTPS address; LangBot Cloud includes one.

Does the Lark (Feishu) bot support streaming replies?

Yes. Enable streaming on the bot; the AI back end must also stream. See the platform feature matrix for details.

Can the same Langflow setup serve other platforms too?

Yes. A pipeline can be bound to many bots, so one configuration can answer on several platforms at once.

Related guides

• Full Lark (Feishu) setup guide
• Full Langflow runner guide
• Other AI back ends on Lark (Feishu): Dify · n8n · Coze · DeepSeek · OpenAI (ChatGPT models)
• Langflow on other platforms: Telegram · Discord · Slack · DingTalk · WeCom (internal app) · WeCom Intelligent Bot