📮 feat: Custom OAuth Headers Support for MCP Server Config

api/server/controllers/UserController.js

@@ -327,30 +327,43 @@ const maybeUninstallOAuthMCP = async (userId, pluginKey, appConfig) => {
   const revocationEndpointAuthMethodsSupported =
     serverConfig.oauth?.revocation_endpoint_auth_methods_supported ??
     clientMetadata.revocation_endpoint_auth_methods_supported;
+  const oauthHeaders = serverConfig.oauth_headers ?? {};
 
   if (tokens?.access_token) {
     try {
-      await MCPOAuthHandler.revokeOAuthToken(serverName, tokens.access_token, 'access', {
-        serverUrl: serverConfig.url,
-        clientId: clientInfo.client_id,
-        clientSecret: clientInfo.client_secret ?? '',
-        revocationEndpoint,
-        revocationEndpointAuthMethodsSupported,
-      });
+      await MCPOAuthHandler.revokeOAuthToken(
+        serverName,
+        tokens.access_token,
+        'access',
+        {
+          serverUrl: serverConfig.url,
+          clientId: clientInfo.client_id,
+          clientSecret: clientInfo.client_secret ?? '',
+          revocationEndpoint,
+          revocationEndpointAuthMethodsSupported,
+        },
+        oauthHeaders,
+      );
     } catch (error) {
       logger.error(`Error revoking OAuth access token for ${serverName}:`, error);
     }
   }
 
   if (tokens?.refresh_token) {
     try {
-      await MCPOAuthHandler.revokeOAuthToken(serverName, tokens.refresh_token, 'refresh', {
-        serverUrl: serverConfig.url,
-        clientId: clientInfo.client_id,
-        clientSecret: clientInfo.client_secret ?? '',
-        revocationEndpoint,
-        revocationEndpointAuthMethodsSupported,
-      });
+      await MCPOAuthHandler.revokeOAuthToken(
+        serverName,
+        tokens.refresh_token,
+        'refresh',
+        {
+          serverUrl: serverConfig.url,
+          clientId: clientInfo.client_id,
+          clientSecret: clientInfo.client_secret ?? '',
+          revocationEndpoint,
+          revocationEndpointAuthMethodsSupported,
+        },
+        oauthHeaders,
+      );
     } catch (error) {
       logger.error(`Error revoking OAuth refresh token for ${serverName}:`, error);
     }

api/server/routes/__tests__/mcp.spec.js

@@ -127,8 +127,13 @@ describe('MCP Routes', () => {
         }),
       };
 
+      const mockMcpManager = {
+        getRawConfig: jest.fn().mockReturnValue({}),
+      };
+
       getLogStores.mockReturnValue({});
       require('~/config').getFlowStateManager.mockReturnValue(mockFlowManager);
+      require('~/config').getMCPManager.mockReturnValue(mockMcpManager);
 
       MCPOAuthHandler.initiateOAuthFlow.mockResolvedValue({
         authorizationUrl: 'https://oauth.example.com/auth',
@@ -146,6 +151,7 @@ describe('MCP Routes', () => {
         'test-server',
         'https://test-server.com',
         'test-user-id',
+        {},
         { clientId: 'test-client-id' },
       );
     });
@@ -314,6 +320,7 @@ describe('MCP Routes', () => {
       };
       const mockMcpManager = {
         getUserConnection: jest.fn().mockResolvedValue(mockUserConnection),
+        getRawConfig: jest.fn().mockReturnValue({}),
       };
       require('~/config').getMCPManager.mockReturnValue(mockMcpManager);
 
@@ -336,6 +343,7 @@ describe('MCP Routes', () => {
         'test-flow-id',
         'test-auth-code',
         mockFlowManager,
+        {},
       );
       expect(MCPTokenStorage.storeTokens).toHaveBeenCalledWith(
         expect.objectContaining({
@@ -392,6 +400,11 @@ describe('MCP Routes', () => {
       getLogStores.mockReturnValue({});
       require('~/config').getFlowStateManager.mockReturnValue(mockFlowManager);
 
+      const mockMcpManager = {
+        getRawConfig: jest.fn().mockReturnValue({}),
+      };
+      require('~/config').getMCPManager.mockReturnValue(mockMcpManager);
+
       const response = await request(app).get('/api/mcp/test-server/oauth/callback').query({
         code: 'test-auth-code',
         state: 'test-flow-id',
@@ -427,6 +440,7 @@ describe('MCP Routes', () => {
 
       const mockMcpManager = {
         getUserConnection: jest.fn().mockRejectedValue(new Error('Reconnection failed')),
+        getRawConfig: jest.fn().mockReturnValue({}),
       };
       require('~/config').getMCPManager.mockReturnValue(mockMcpManager);
 
@@ -1234,6 +1248,7 @@ describe('MCP Routes', () => {
         getUserConnection: jest.fn().mockResolvedValue({
           fetchTools: jest.fn().mockResolvedValue([]),
         }),
+        getRawConfig: jest.fn().mockReturnValue({}),
       };
       require('~/config').getMCPManager.mockReturnValue(mockMcpManager);
 
@@ -1281,6 +1296,7 @@ describe('MCP Routes', () => {
             .fn()
             .mockResolvedValue([{ name: 'test-tool', description: 'Test tool' }]),
         }),
+        getRawConfig: jest.fn().mockReturnValue({}),
       };
       require('~/config').getMCPManager.mockReturnValue(mockMcpManager);
 

api/server/routes/mcp.js

@@ -65,6 +65,7 @@ router.get('/:serverName/oauth/initiate', requireJwtAuth, async (req, res) => {
       serverName,
       serverUrl,
       userId,
+      getOAuthHeaders(serverName),
       oauthConfig,
     );
 
@@ -132,7 +133,12 @@ router.get('/:serverName/oauth/callback', async (req, res) => {
     });
 
     logger.debug('[MCP OAuth] Completing OAuth flow');
-    const tokens = await MCPOAuthHandler.completeOAuthFlow(flowId, code, flowManager);
+    const tokens = await MCPOAuthHandler.completeOAuthFlow(
+      flowId,
+      code,
+      flowManager,
+      getOAuthHeaders(serverName),
+    );
     logger.info('[MCP OAuth] OAuth flow completed, tokens received in callback route');
 
     /** Persist tokens immediately so reconnection uses fresh credentials */
@@ -538,4 +544,10 @@ router.get('/:serverName/auth-values', requireJwtAuth, async (req, res) => {
   }
 });
 
+function getOAuthHeaders(serverName) {
+  const mcpManager = getMCPManager();
+  const serverConfig = mcpManager.getRawConfig(serverName);
+  return serverConfig?.oauth_headers ?? {};
+}
+
 module.exports = router;

packages/api/src/mcp/MCPConnectionFactory.ts

@@ -142,6 +142,7 @@ export class MCPConnectionFactory {
           serverName: metadata.serverName,
           clientInfo: metadata.clientInfo,
         },
+        this.serverConfig.oauth_headers ?? {},
         this.serverConfig.oauth,
       );
     };
@@ -161,6 +162,7 @@ export class MCPConnectionFactory {
               this.serverName,
               data.serverUrl || '',
               this.userId!,
+              config?.oauth_headers ?? {},
               config?.oauth,
             );
 
@@ -358,6 +360,7 @@ export class MCPConnectionFactory {
         this.serverName,
         serverUrl,
         this.userId!,
+        this.serverConfig.oauth_headers ?? {},
         this.serverConfig.oauth,
       );
 

packages/api/src/mcp/__tests__/MCPConnectionFactory.test.ts

@@ -255,6 +255,7 @@ describe('MCPConnectionFactory', () => {
         'test-server',
         'https://api.example.com',
         'user123',
+        {},
         undefined,
       );
       expect(oauthOptions.oauthStart).toHaveBeenCalledWith('https://auth.example.com');