fx vs stitch-skills: Features, Pricing & Which Is Better (2026)

A side-by-side comparison of fx and stitch-skills — features, pricing, and ideal use cases — to help you decide which AI tool fits your workflow.

fx

Vercel Labs

Free

Vercel Labs' tiny open-source coding agent — a ~6 MB native CLI written in Zig, built for speed, embeddability and Unix-style ergonomics.

Tiny Native Binary: The whole agent ships as a roughly 6 MB executable designed for instant installation and for embedding in resource-constrained environments and agent sandboxes.
Instant Time to Prompt: fx cold starts in about 10 microseconds and performs no unnecessary work or I/O before accepting user input, which matters for programmatic invocation.
Minimal Memory Footprint: A single-digit-megabyte memory baseline lets you pack many concurrent instances onto one machine.
Shell-Like Ergonomics: Scroll history is preserved by default and output is deliberately sparse, so the CLI composes like a Unix tool instead of taking over the terminal.
Context Efficiency: A minimal system prompt and tool surface reduce token spend and improve time-to-first-token performance.
WebAssembly Builds: Optimal fx.wasm builds from the Zig toolchain shrink the binary further and make the network stack pluggable, enabling the in-browser demo.
Model and Provider Agnostic: Works with local models, LLM gateways, direct provider API access or existing subscriptions rather than locking you to one vendor.
Extensible Small Core: Capabilities are added through skills, plugins and MCPs, following a Unix-like philosophy of a small core with composable extensions.

Sandboxed Agent Execution: Ship a full coding agent inside a container or sandbox where a large runtime would not fit.
Embedding in Larger Systems: Use fx as the agent harness inside your own product or internal platform rather than building a loop from scratch.
CI and Scripted Automation: Invoke a coding agent from pipelines and scripts where fast cold starts and quiet output matter more than an interactive UI.
Agent Harness Research: Experiment with system prompt and tool design on a deliberately minimal, readable Apache-2.0 codebase.
Local-Model Coding: Run agentic coding against a locally hosted model without any dependency on a specific cloud provider.
Browser-Based Demos and Playgrounds: Compile to WebAssembly and run the agent client-side with networking delegated to browser fetch.

Google Labs Code

Free

Open-source collection of agent skills and plugins for Google Stitch that plug into Codex, Claude Code, Cursor, and Gemini CLI.

Cross-Agent Plugin Bundles: Ships stitch-design, stitch-build, and stitch-utilities as marketplace plugins that install into Codex, Claude Code, Cursor, Antigravity, or Gemini CLI.
Code to Design: Convert frontend code (React, Vue, etc.) into a Stitch design by extracting HTML, applying the design system, and uploading it to a Stitch project.
Generate Design: Create new screens from text or images, edit existing screens, and produce dark-mode or high-density design variants.
Design System Management: Upload a DESIGN.md and apply the theme across all screens in a Stitch project.
Extract Design MD: Scan a codebase and generate a comprehensive DESIGN.md describing the design system directly from source.
Static HTML Extraction: Capture self-contained static HTML from running web apps with CSS and images inlined for handoff.
React / React Native / shadcn Codegen: Convert Stitch designs to production-ready React components, React Native code, or shadcn/ui-integrated apps.
Remotion Walkthrough Videos: Generate video walkthroughs of a Stitch project with smooth transitions and zooming.

Migrating a Codebase to a Design System: Upload an existing frontend into Stitch to run a design migration project with consistent tokens and theming.
Rapid Screen Generation: Product teams generate mobile or web screens from short prompts and iterate on variants without leaving the coding agent.
Code Handoff from Design: Convert Stitch screens into React or React Native components so engineers can consume the design in the target framework.
Design System Extraction: Reverse-engineer a DESIGN.md from an existing repo to formalize implicit design tokens and share them across teams.
Design Reviews and Walkthroughs: Automatically produce video walkthroughs of a project to share with stakeholders and reviewers.
Agent-Native Workflows: Developers who live inside Claude Code, Cursor, or Codex install Stitch skills locally to drive design work from the same agent they use for coding.