diff --git a/packages/api/src/mcp/__tests__/MCPOAuthClientRegistrationReuse.test.ts b/packages/api/src/mcp/__tests__/MCPOAuthClientRegistrationReuse.test.ts
index 507be31f3a..da69a5060f 100644
--- a/packages/api/src/mcp/__tests__/MCPOAuthClientRegistrationReuse.test.ts
+++ b/packages/api/src/mcp/__tests__/MCPOAuthClientRegistrationReuse.test.ts
@@ -23,6 +23,7 @@
  * fix and would require a distributed lock (e.g., Redis SETNX) around registration.
  */
 
+import type { OAuthClientInformation } from '@modelcontextprotocol/sdk/shared/auth.js';
 import type { OAuthTestServer } from './helpers/oauthTestServer';
 import { InMemoryTokenStore, createOAuthMCPServer } from './helpers/oauthTestServer';
 import { MCPOAuthHandler, MCPTokenStorage } from '~/mcp/oauth';
@@ -210,7 +211,7 @@ describe('MCPOAuthHandler - client registration reuse on reconnection', () => {
           client_id: 'old-client-id',
           client_secret: 'old-secret',
           redirect_uris: ['http://old-domain.com/api/mcp/test-server/oauth/callback'],
-        },
+        } as OAuthClientInformation & { redirect_uris: string[] },
       });
 
       const result = await MCPOAuthHandler.initiateOAuthFlow(
@@ -242,7 +243,7 @@ describe('MCPOAuthHandler - client registration reuse on reconnection', () => {
           client_id: 'empty-redirect-client',
           client_secret: 'secret',
           redirect_uris: [],
-        },
+        } as OAuthClientInformation & { redirect_uris: string[] },
       });
 
       const result = await MCPOAuthHandler.initiateOAuthFlow(
diff --git a/packages/api/src/mcp/oauth/handler.ts b/packages/api/src/mcp/oauth/handler.ts
index bc351d9660..db6cf50697 100644
--- a/packages/api/src/mcp/oauth/handler.ts
+++ b/packages/api/src/mcp/oauth/handler.ts
@@ -509,7 +509,8 @@ export class MCPOAuthHandler {
             findToken,
           });
           if (existing?.clientInfo?.client_id) {
-            const storedRedirectUri = existing.clientInfo.redirect_uris?.[0];
+            const storedRedirectUri = (existing.clientInfo as OAuthClientInformation)
+              .redirect_uris?.[0];
             if (!storedRedirectUri || storedRedirectUri !== redirectUri) {
               logger.debug(
                 `[MCPOAuth] Stored redirect_uri "${storedRedirectUri}" differs from current "${redirectUri}", will re-register`,