Side-by-side
assistant-ui vs Copilot Extensions Preview SDK (JS)
assistant-ui (7.1/10) wins on adoption; Copilot Extensions Preview SDK (JS) (7.5/10) leads on safety and documentation.
Both are scored on the same Skill Score v2 rubric — effectiveness 40% / safety 25% / maintenance 15% / documentation 15% / adoption 5% once benchmarked, or safety 40% / maintenance 30% / documentation 30% while provisional — so every comparison below is apples-to-apples. How we score.
Choose
assistant-ui
Choose assistant-ui if you weight adoption most.
Choose
Copilot Extensions Preview SDK (JS)
Choose Copilot Extensions Preview SDK (JS) if you weight safety and documentation most.
Effectively tied on: maintenance.
| Dimension | assistant-uiassistant-ui | Copilot Extensions Preview SDK (JS)GitHub copilot-extensions |
|---|---|---|
| Skill score (overall) | 7.1 | 7.5 |
| Safety sub-score | 75/100 | 95/100 |
| Maintenance sub-score | 54/100 | 54/100 |
| Documentation sub-score | 80/100 | 88/100 |
| Adoption sub-score | 74/100 | 52/100 |
| Community rating | No ratings yet | No ratings yet |
| Known advisories (CVEs) | None known | None known |
| Platforms | Other | Copilot |
| Primary platform | Other Agent Tools | GitHub Copilot Extensions |
| Vendor | assistant-ui | GitHub copilot-extensions |
| Primary category | Engineering and Development | Engineering and Development |
| License | MIT | MIT |
| GitHub stars | 10.2K | 87 |
| Last commit | 1 month ago | 5 months ago |
| Last verified | Jul 5, 2026 | Jul 5, 2026 |
| Open flags | None | None |
Frequently asked
Is assistant-ui or Copilot Extensions Preview SDK (JS) better?
assistant-ui (7.1/10) wins on adoption; Copilot Extensions Preview SDK (JS) (7.5/10) leads on safety and documentation.
What's the difference between assistant-ui and Copilot Extensions Preview SDK (JS)?
assistant-ui leads on adoption; Copilot Extensions Preview SDK (JS) leads on safety, documentation; they're effectively tied on maintenance. Both are scored on the same Skill Score v2 rubric — measured effectiveness (when benchmarked) plus safety, maintenance, and documentation, with popularity as context only — so the comparison is like-for-like.
Which has a higher Skill Score, assistant-ui or Copilot Extensions Preview SDK (JS)?
Copilot Extensions Preview SDK (JS) scores higher (7.5/10 vs 7.1/10).