Echo

Build AI apps without fronting the bill. Echo handles auth, billing, and metering so users pay for their own usage and you never touch infrastructure costs.

The problem with AI apps

Generative AI is changing the way we build apps. Build a strong UX, call out to powerful models over API and ship value to your users.

But these APIs are expensive and you, the developer, pay the bill.

You need to be prepared to

Front API costs
Manage API keys
Cap usage from power users
Build per-user auth, metering and billing
Integrate Stripe

Drop in Echo as a replacement for the Vercel AI SDK and add an Echo Sign-In component. When users call OpenAI (or the other 100+ models we support), requests route through Echo and they pay for their own usage. You never front the costs.

Set a markup percentage (e.g. 50%), and every token your users consume generates instant revenue. Echo settles the provider bill and returns your profit.

No suprise bills, no API keys, no Stripe integration, and no infrastructure costs.

Starting Fresh

To get started on a new app, use the echo-start CLI tool, which scaffolds a pre-configured Echo project:

npx echo-start@latest --template next

yarn dlx echo-start@latest --template next

pnpx echo-start@latest --template next

bunx echo-start@latest --template next

This will create a new Next.js app with Echo integration ready to go. For other templates and frameworks, check out our templates section.

Existing Apps

Three integration patterns:

Next.js SDK — Server-side auth with automatic token management
React SDK — OAuth2 + PKCE for secure client-side LLM calls
TypeScript SDK — API keys for backends and CLI tools

The React and Next.js SDKs are opinionated wrappers around the TypeScript SDK, providing framework-specific patterns while the TypeScript SDK offers direct API access for maximum flexibility.