How to connect Open WebUI to Anchor
Step-by-step setup for every MCP-compatible agent. One URL, OAuth sign-in, and you're done.
Open WebUI
An admin completes the one-time server setup, then each user enables Anchor per-chat.
Admin setup
- Go to Admin Panel → Settings → Integrations → Manage Tool Servers and click the + button.
- Fill in the Add Connection dialog:
- Type: MCP Streamable HTTP
- Name: Anchor
- ID: any non-empty value (e.g.
openwebui). Required — Open WebUI won't persist the connection while ID is empty (even with a valid URL, Save silently does nothing). The value itself doesn't matter. - URL:
- Auth: OAuth 2.1
- Click Register Client (top-right of the Auth row). Wait for the badge to flip from orange Not Registered to green Registered.
- Click Save.
Enable write tools (Function Calling: Native)
By default a model may use the legacy Default (prompt-based) function-calling mode. In that mode it reliably calls read-only tools like ls and read_file but silently fails to call write tools like write_file, mkdir, and mv — so it looks like Anchor can only read. Switch the model to Native function calling so all tools work.
- Go to Admin Panel → Settings → Models and select the model.
- Under Advanced Params, click Show.
- Set Function Calling to Native.
- Click Save & Update.
Note: the model itself must support native tool calling. After switching to Native, every Anchor tool (read and write) works.
Per-chat usage
- Start a New Chat.
- Click the wrench icon in the chat box (bottom-left of the message input).
- Toggle Anchor on under Available Tools.
- Pick a tool-capable model from the model dropdown (e.g.
anthropic/claude-sonnet-4-5). - Ask "List my Anchor orgs." The first time, a sign-in window opens — use your Anchor account to connect.
- Ask "What is Anchor, and what can I use it for?"