Web fetch & MCP
Outbound network features have hard safety guards. Most surprises trace back to one of those guards firing.
Pasted URL is ignored
Your prompt has a link but the model only sees the bare URL, not the page content.
- Web fetch is off by default. Turn it on in Settings → Tools → Web fetch.
- Only
http://andhttps://URLs are fetched. - Up to 5 URLs per message are followed. Extras are ignored.
“URL blocked” for localhost, 192.168.x, or my office VPN
Loach refuses to fetch an internal URL.
This is intentional. The SSRF guard rejects any URL whose resolved IP lands on loopback, link-local, or private RFC1918 ranges, even if the hostname looks public but resolves there via DNS. To share internal content with a model, copy the page text and paste it into the chat instead.
A URL fetch silently produces a “fetch failed” stub
The model is told a URL was attempted but no content came back.
The fetch hit a limit:
- 30 s total timeout or 10 s connect timeout,
- 5 MB body cap,
- A non-2xx HTTP response.
Try the URL in a browser. If it works there but not in Loach, the page is likely slow, large, or blocks non-browser user agents.
MCP “Test connection” fails
An MCP server is configured but the test button reports an error.
- Confirm the URL is the Streamable-HTTP endpoint. Loach does not support stdio or SSE MCP transports.
- If the server requires auth, add an
Authorizationheader in the server’s row. - Check that the response body fits under 4 MB — misconfigured servers that dump full schemas can exceed this.
- Per-request timeout is 30 s.