From 24179cde2f9e004ab5db38a323998ad6fb992ad4 Mon Sep 17 00:00:00 2001
From: Varun Chawla <34209028+veeceey@users.noreply.github.com>
Date: Sun, 15 Feb 2026 17:09:41 -0800
Subject: [PATCH] fix: preserve trailing slash in MCP server URLs (#21212)

Stop trimming trailing slashes from MCP server URLs on save. Some MCP
servers (e.g. Bitrix24) require a trailing slash; removing it triggers a
301 redirect that drops Authorization headers, resulting in 400 errors.

The trailing-slash trim is now skipped when the connection type is 'mcp',
while OpenAPI connections continue to have it stripped as before.

Fixes open-webui#21179
---
 src/lib/components/AddToolServerModal.svelte | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/lib/components/AddToolServerModal.svelte b/src/lib/components/AddToolServerModal.svelte
index 5b64b692a..555d8ff8e 100644
--- a/src/lib/components/AddToolServerModal.svelte
+++ b/src/lib/components/AddToolServerModal.svelte
@@ -250,8 +250,12 @@
 	const submitHandler = async () => {
 		loading = true;
 
-		// remove trailing slash from url
-		url = url.replace(/\/$/, '');
+		// remove trailing slash from url for non-MCP connections
+		// MCP servers may require a trailing slash; stripping it can cause
+		// 301 redirects that lose auth headers (see #21179)
+		if (type !== 'mcp') {
+			url = url.replace(/\/$/, '');
+		}
 		if (id.includes(':') || id.includes('|')) {
 			toast.error($i18n.t('ID cannot contain ":" or "|" characters'));
 			loading = false;