diff --git a/src/server/parallel.ts b/src/server/parallel.ts
index cf6f6131..177b2b0c 100644
--- a/src/server/parallel.ts
+++ b/src/server/parallel.ts
@@ -9,9 +9,16 @@ export interface WebConfig {
   parallelApiKey?: string;
 }
 export function webSearchProvider(value?: string): WebSearchProvider {
-  if (!value) return 'parallel';
-  if (value === 'parallel' || value === 'browser' || value === 'disabled')
-    return value;
+  // Tolerate surrounding whitespace from .env files, matching the other
+  // environment parsers; a blank value falls back to the default.
+  const normalized = value?.trim();
+  if (!normalized) return 'parallel';
+  if (
+    normalized === 'parallel' ||
+    normalized === 'browser' ||
+    normalized === 'disabled'
+  )
+    return normalized;
   throw new Error(
     'WEB_SEARCH_PROVIDER must be parallel, browser, or disabled.',
   );
diff --git a/tests/parallel.test.ts b/tests/parallel.test.ts
index 82e79e9e..44c682b1 100644
--- a/tests/parallel.test.ts
+++ b/tests/parallel.test.ts
@@ -40,6 +40,11 @@ describe('Parallel research', () => {
     expect(webSearchProvider('disabled')).toBe('disabled');
     expect(() => webSearchProvider('other')).toThrow('WEB_SEARCH_PROVIDER');
   });
+  it('tolerates surrounding whitespace from .env values', () => {
+    expect(webSearchProvider('  browser  ')).toBe('browser');
+    expect(webSearchProvider('disabled\n')).toBe('disabled');
+    expect(webSearchProvider('   ')).toBe('parallel');
+  });
   it('searches, extracts and grounds a topic-only brief without a browser', async () => {
     mcp.callTool
       .mockResolvedValueOnce(result(page(), page('https://example.org')))