AI Plugin IndexMCP Extensions vs Harness
MCP Extensions and Harness are both ai and llm tools MCP servers. Harness scores higher (95 vs 91 out of 100). Harness has more GitHub stars (1.3k), and Harness was updated more recently (4 days ago). The table compares them side by side.
| MCP Extensions | Harness | |
|---|---|---|
| Score | 91 / 100 | 95 / 100 |
| What it does | OpenAI extensions for MCP servers and apps. | Start Claude Code and Codex agents the person can watch, wait for them and read their answers. |
| Publisher | Verified: npm:@openai | Verified: harness.autonomous.ai |
| Grades | Maintenance A, Licence A, Quality B | Maintenance A, Licence A, Quality A |
| npm downloads a week | 64,945 | Not on npm |
| Runs | Local | Local |
| Works with | Claude Code, Claude Desktop, Cursor, Codex, Gemini CLI, VS Code, Windsurf | Claude Code, Claude Desktop, Cursor, Codex, Gemini CLI, VS Code, Windsurf |
| GitHub stars | 1,090 | 1,320 |
| Last commit | 10 Oct 2026 | 19 Oct 2026 |
| Licence | Apache-2.0 | MIT |
| Listed since | 20 Oct 2026 | 19 Oct 2026 |
| Install MCP Extensions | Install Harness |
Questions
Is MCP Extensions or Harness more popular?
Harness has more GitHub stars: 1,320.
Can I use MCP Extensions and Harness together?
Yes. AI assistants can load several MCP servers at once. Install both and the assistant picks the right one for each task.