Connect n8n to Mattermost

This recipe puts your n8n app behind a Mattermost bot. LangBot receives messages from Mattermost, runs them through a pipeline, and sends the answer back, so you do not write any platform code.

n8n runs the workflow; LangBot handles the chat platform, sessions and delivery and calls your workflow through a webhook 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 n8n account or instance that LangBot can reach over the network.
• A Mattermost bot account (role Member) and its access token, plus your Mattermost server URL.

Networking

LangBot only needs to reach your Mattermost server; Mattermost does not need to reach LangBot.

1. Prepare n8n

1. Start the workflow with a Webhook or On chat message trigger. Set Response Mode to Streaming if you want streamed replies.
2. Answer with an AI Agent node (streaming) or a Respond to Webhook node whose response key matches LangBot's output key.
3. Click Active to enable the workflow and copy its production webhook URL.

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 Mattermost bot

1. Create the bot account in Mattermost (choose post:all for direct messages) and copy its token; it is shown only once.
2. Create a bot with the Mattermost adapter, enter the server address and token, and bind a pipeline.

4. Bind and test

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

Send the bot a direct message, or mention it in a channel it has joined.

Troubleshooting

• Empty replies: the key in Respond to Webhook must match the output key configured in LangBot.
• The test URL only works while the n8n editor is listening; use the production URL of an active workflow.
• Administrator-related features are not supported; keep the bot role as Member.
• Disable streaming on the bot if your pipeline or AI provider does not support it.
• 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 Mattermost?

No. LangBot only needs to reach your Mattermost server; Mattermost does not need to reach LangBot.

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