tsconfig with jasmine or mocha 1. tsconfig.json (Use with Caution): As mentioned earlier, modifying tsconfig.json is generally not the best approach. However, if all else fails, you can try these options: types array: Explicitly list only the types you want to include. In your tsconfig.json, add or modify the types array: JSON {  "compilerOptions": {  // ... other options  "types": ["mocha"] // Only include Mocha types  } } typeRoots array: Specify the directories where TypeScript should look for type definitions. This can help you control which type definitions are loaded. JSON {  "compilerOptions": {  // ... other options  "typeRoots": ["./node_modules/@types"] // Only look in node_modules/@types  } } 2. Troubleshooting Tips: Clean Install: Always perform a clean install (rm -rf node_modules && npm install) after making changes to dependencies. VS Code Extensions: If you have any VS code extensions that might be influencing typescript, disable them to test if they are contributing to the issue. 3.Restart TypeScript Server:  In VS Code, use "TypeScript: Restart TS Server" from the command palette. By systematically working through these steps, you should be able to identify and eliminate the source of the duplicate type definitions.