[GH-ISSUE #24113] feat: Mattermost sidebar tab — embedded team messaging and AI agent communication #35722

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GiteaMirror · 2026-04-25T09:53:53-05:00

GiteaMirror commented

2026-04-25 09:53:53 -05:00

Originally created by @githb-ac on GitHub (Apr 24, 2026).
Original GitHub issue: https://github.com/open-webui/open-webui/issues/24113

Check Existing Issues

I have searched for all existing open AND closed issues and discussions for similar requests. I have found none that is comparable to my request.

Verify Feature Scope

I have read through and understood the scope definition for feature requests in the Issues section. I believe my feature request meets the definition and belongs in the Issues section instead of the Discussions.

Problem Description

Users running agent pipelines in Open WebUI have no way to surface team
communications alongside their agent activity. Mattermost is a free, self-hosted,
open-source team messaging platform (Slack alternative) that pairs naturally with
an AI agent — agents can post task completions, alerts, and updates directly to
Mattermost channels.

Mattermost integration is already implemented natively in Hermes Agent by Nous
Research (https://github.com/NousResearch/hermes-agent/blob/main/gateway/platforms/mattermost.py),
the leading open-source AI agent framework, demonstrating that the Mattermost ↔ AI
agent communication pattern is proven and production-ready. This feature request
asks for that same capability to be surfaced natively inside Open WebUI.

Currently there is no way to view Mattermost or connect it to Open WebUI agents
without leaving the interface entirely.

Desired Solution you'd like

Two complementary additions:

Part 1 — Embedded Mattermost sidebar tab:
Add a Mattermost tab rendered as an iframe pointed at the user's configured
Mattermost URL. The full Mattermost interface — channels, direct messages,
notifications, admin panel — appears inside Open WebUI automatically.

mattermost_url — base URL of the user's Mattermost instance (e.g. http://localhost:8065)
mattermost_tab_enabled — toggle to show/hide the tab

Part 2 — MCP server integration:
The recommended MCP server for connecting agents to Mattermost is the third-party
mattermost-mcp (https://github.com/pvev/mattermost-mcp), preferred for its stdio
compatibility. When routed through mcp2cli (https://github.com/knowsuchagency/mcp2cli),
it connects without loading the full tool schema into context — delivering
approximately 99% token usage savings compared to a standard MCP connection.

Recommended stack:
mattermost-mcp (stdio) → mcp2cli → Open WebUI agent

The MCP server management panel should surface mattermost-mcp as a recognised
integration with a one-click install, pre-configured to route through mcp2cli.

What agents can do via Mattermost MCP:

Post messages to channels
Read channel history
Send direct messages
React to messages
Create and manage channels
Search message history

Alternatives Considered

Currently the only alternative is opening Mattermost in a separate browser tab
and manually configuring the MCP server without guidance. The 99% token saving
from mcp2cli stdio routing is not documented or surfaced anywhere in the current UI.

Additional Context

Mattermost native agent integration precedent (Hermes Agent):
https://github.com/NousResearch/hermes-agent/blob/main/gateway/platforms/mattermost.py

Mattermost Team Edition is completely free and self-hostable: https://mattermost.com/
Full documentation: https://docs.mattermost.com/
Recommended MCP server: https://github.com/pvev/mattermost-mcp
mcp2cli for stdio routing: https://github.com/knowsuchagency/mcp2cli

Attached dashboard shows the proposed Mattermost tab layout.
owui-aegis-app-data-v5.html

Originally created by @githb-ac on GitHub (Apr 24, 2026). Original GitHub issue: https://github.com/open-webui/open-webui/issues/24113 ### Check Existing Issues - [x] I have searched for all existing **open AND closed** issues and discussions for similar requests. I have found none that is comparable to my request. ### Verify Feature Scope - [x] I have read through and understood the scope definition for feature requests in the Issues section. I believe my feature request meets the definition and belongs in the Issues section instead of the Discussions. ### Problem Description Users running agent pipelines in Open WebUI have no way to surface team communications alongside their agent activity. Mattermost is a free, self-hosted, open-source team messaging platform (Slack alternative) that pairs naturally with an AI agent — agents can post task completions, alerts, and updates directly to Mattermost channels. Mattermost integration is already implemented natively in Hermes Agent by Nous Research (https://github.com/NousResearch/hermes-agent/blob/main/gateway/platforms/mattermost.py), the leading open-source AI agent framework, demonstrating that the Mattermost ↔ AI agent communication pattern is proven and production-ready. This feature request asks for that same capability to be surfaced natively inside Open WebUI. Currently there is no way to view Mattermost or connect it to Open WebUI agents without leaving the interface entirely. ### Desired Solution you'd like Two complementary additions: Part 1 — Embedded Mattermost sidebar tab: Add a Mattermost tab rendered as an iframe pointed at the user's configured Mattermost URL. The full Mattermost interface — channels, direct messages, notifications, admin panel — appears inside Open WebUI automatically. - mattermost_url — base URL of the user's Mattermost instance (e.g. http://localhost:8065) - mattermost_tab_enabled — toggle to show/hide the tab Part 2 — MCP server integration: The recommended MCP server for connecting agents to Mattermost is the third-party mattermost-mcp (https://github.com/pvev/mattermost-mcp), preferred for its stdio compatibility. When routed through mcp2cli (https://github.com/knowsuchagency/mcp2cli), it connects without loading the full tool schema into context — delivering approximately 99% token usage savings compared to a standard MCP connection. Recommended stack: mattermost-mcp (stdio) → mcp2cli → Open WebUI agent The MCP server management panel should surface mattermost-mcp as a recognised integration with a one-click install, pre-configured to route through mcp2cli. What agents can do via Mattermost MCP: - Post messages to channels - Read channel history - Send direct messages - React to messages - Create and manage channels - Search message history ### Alternatives Considered Currently the only alternative is opening Mattermost in a separate browser tab and manually configuring the MCP server without guidance. The 99% token saving from mcp2cli stdio routing is not documented or surfaced anywhere in the current UI. ### Additional Context Mattermost native agent integration precedent (Hermes Agent): https://github.com/NousResearch/hermes-agent/blob/main/gateway/platforms/mattermost.py Mattermost Team Edition is completely free and self-hostable: https://mattermost.com/ Full documentation: https://docs.mattermost.com/ Recommended MCP server: https://github.com/pvev/mattermost-mcp mcp2cli for stdio routing: https://github.com/knowsuchagency/mcp2cli Attached dashboard shows the proposed Mattermost tab layout. [owui-aegis-app-data-v5.html](https://github.com/user-attachments/files/27069165/owui-aegis-app-data-v5.html)

GiteaMirror commented

2026-04-25 09:53:54 -05:00

@Classic298 commented on GitHub (Apr 25, 2026):

Consider using tools for this. Also out of scope for issues section

@Classic298 commented on GitHub (Apr 25, 2026): Consider using tools for this. Also out of scope for issues section

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Reference: github-starred/open-webui#35722