Build a Lark (Feishu) AI Bot with OpenAI (ChatGPT models)
Step-by-step guide to running a OpenAI (ChatGPT models)-powered AI bot on Lark (Feishu) with LangBot: model setup, bot credentials, networking, testing and troubleshooting.
This recipe puts a OpenAI (ChatGPT models) model 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.
Use OpenAI's GPT models with LangBot's built-in Agent, with optional knowledge bases, MCP tools, Skills and a code sandbox.
What you need
- A running LangBot instance: LangBot Cloud (no server needed) or a self-hosted deployment with Docker or
uvx langbot. - A OpenAI (ChatGPT models) account or server you can call from LangBot.
- A Feishu or Lark custom app (
app_idandapp_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. Add the OpenAI (ChatGPT models) model
- Create an API key in the OpenAI console.
- In LangBot, open Models, add an LLM model with the provider set to OpenAI and request URL
https://api.openai.com/v1, then paste the API key and the model ID. - Enable Tool Use if the model supports function calling; MCP tools, Skills and the sandbox need it.
- Use a current model ID from OpenAI's model list. Any OpenAI-compatible endpoint works the same way with its own request URL.
2. Create a pipeline
Open Pipelines in the LangBot WebUI, create a pipeline (or edit the default one) and set AI as follows.
| Field | Value |
|---|---|
| Runner | Local Agent (built-in Agent) |
| Model | The model you just added. You can add fallback models. |
| Prompt | Instructions: who the bot is, tone, what it must not do. |
| Knowledge Bases | Optional. Attach a knowledge base so answers come from your documents. |
3. Create the Lark (Feishu) bot
- Create a bot with the Lark adapter, select the platform domain (Feishu or Lark) and use One-Click Setup, or enter
app_idandapp_secretmanually. - 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
- Region or network errors: LangBot must be able to reach the request URL. Behind a restricted network, use a compatible gateway you can reach.
- 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 OpenAI (ChatGPT models) 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
- Model configuration
- Other AI back ends on Lark (Feishu): Dify · n8n · Coze · Langflow · DeepSeek
- OpenAI (ChatGPT models) on other platforms: Telegram · Discord · Slack · DingTalk · WeCom (internal app) · WeCom Intelligent Bot
Build a Slack AI Bot with OpenAI (ChatGPT models)
Step-by-step guide to running a OpenAI (ChatGPT models)-powered AI bot on Slack with LangBot: model setup, bot credentials, networking, testing and troubleshooting.
Build a DingTalk AI Bot with OpenAI (ChatGPT models)
Step-by-step guide to running a OpenAI (ChatGPT models)-powered AI bot on DingTalk with LangBot: model setup, bot credentials, networking, testing and troubleshooting.
