fx (by Vercel) vs. Pi

Feature	fx (by Vercel)	Pi

Tagline	Tiny, open, embeddable, native coding agent by Vercel.	A minimal terminal coding harness
Website	https://fx.sh	https://pi.dev
Language	zig	typescript
Release Date	August 17, 2026	December 2, 2025
Last Updated	August 19, 2026	June 28, 2026
Provider Type	Independent	Independent
MCP Support	Yes	No
Multi-Agent Support	No	Yes
Git Integration	minimal	deep
Multi-File Editing	Yes	Yes
Auto Test Running	No	Yes
Sandbox / Permissions	Yes	Yes
Image / Multimodal Input	Yes	Yes
Voice Mode	No	No
IDE Integration		None - terminal only
Hooks / Extensions	No	Yes
Web Search	Yes	Yes
Local Model Support	Yes	Yes
Context Window	Model dependent	Model-dependent; auto-compaction
Supported Models	All Vercel AI Gateway supported models, including OpenAI, Anthropic, Google, DeepSeek, z.AI, Moonshot, etc	20+ providers: Anthropic, OpenAI, Google, Mistral, OpenRouter, Groq, Ollama, xAI, Azure, Bedrock
Supported Subscriptions	—	GitHub Copilot Claude Code ChatGPT
Pricing Model	Free, BYOK, Usage Based	BYOK
Free Tier	No	Yes
Price Range	0 - $20 / mo / Custom (Vercel AI Gateway)	Free (BYOK)
Source Code Availability	Open Source (Apache-2.0)	Open Source (MIT)
Source Code	https://github.com/vercel-labs/fx	https://github.com/badlogic/pi-mono
Development State	active	active