Amp vs. fx (by Vercel)

Feature	Amp	fx (by Vercel)

Tagline	The frontier coding agent	Tiny, open, embeddable, native coding agent by Vercel.
Website	https://ampcode.com	https://fx.sh
Language	typescript	zig
Release Date	April 14, 2025	August 17, 2026
Last Updated	June 29, 2026	August 19, 2026
Provider Type	AI Lab	Independent
MCP Support	Yes	Yes
Multi-Agent Support	Yes	No
Git Integration	deep	minimal
Multi-File Editing	Yes	Yes
Auto Test Running	Yes	No
Sandbox / Permissions	Yes	Yes
Image / Multimodal Input	Yes	Yes
Voice Mode	No	No
IDE Integration	VS Code
Hooks / Extensions	Yes	No
Web Search	Yes	Yes
Local Model Support	No	Yes
Context Window	Model-dependent	Model dependent
Supported Models	Claude Opus 4.8, GPT-5.5, GPT-5.3-Codex, Gemini 3.1 Pro / Flash	All Vercel AI Gateway supported models, including OpenAI, Anthropic, Google, DeepSeek, z.AI, Moonshot, etc
Pricing Model	Usage Based	Free, BYOK, Usage Based
Free Tier	Yes	No
Price Range	Free daily grant, then usage-based	0 - $20 / mo / Custom (Vercel AI Gateway)
Source Code Availability	Proprietary Software	Open Source (Apache-2.0)
Source Code		https://github.com/vercel-labs/fx
Development State	active	active