revert: drop validateToolOutput drive-by, leave to #2106

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: cogeor

src/server/mcp.ts

@@ -306,11 +306,8 @@ export class McpServer {
         }
 
         // if the tool has an output schema, validate structured content
-        // Same fallback as validateToolInput: when normalizeObjectSchema returns undefined
-        // (wrapped schema), parse against the original to avoid passing undefined into safeParseAsync.
-        const outputObj = normalizeObjectSchema(tool.outputSchema);
-        const schemaToParse = outputObj ?? (tool.outputSchema as AnySchema);
-        const parseResult = await safeParseAsync(schemaToParse, result.structuredContent);
+        const outputObj = normalizeObjectSchema(tool.outputSchema) as AnyObjectSchema;
+        const parseResult = await safeParseAsync(outputObj, result.structuredContent);
         if (!parseResult.success) {
             const error = 'error' in parseResult ? parseResult.error : 'Unknown error';
             const errorMessage = getParseErrorMessage(error);