How do I connect an API to Lovable?

The general pattern

Most third-party APIs connect to a Lovable app the same way:

1. Get an API key or credentials from the provider.
2. Ask Lovable to store it as a secret (server-side, never in front-end code).
3. Ask Lovable to create a server function that calls the API using that secret.
4. Have your UI call your own server function, not the third-party API directly.

"Add a server function that calls [API name]'s endpoint to [do X], store the API key as a secret, and show the result on the [page name] page."

Why the extra hop matters

Browsers can read any key placed in front-end code. Routing calls through a Lovable Cloud (or your own Supabase project) server/edge function keeps the key private and lets you add checks — rate limiting, validating input, logging — before the request goes out.

What Lovable needs from you

• The exact endpoint, method, and required parameters.
• Authentication style (API key header, OAuth token, bearer token).
• What the response should populate in your UI.
• Whether the call happens on page load, on a user action, or on a schedule.

Common integrations already documented

Lovable has first-class connectors for some services (Stripe, Resend, GitHub, Google Suite) accessible from the integrations panel. For anything else, a generic REST call through a server function works the same way — see /questions/how-do-i-securely-call-third-party-apis for the security details.

What usually goes wrong

• Pasting the key into a component or .env file exposed to the client — always ask for it as a secret instead.
• Forgetting CORS: calling a third-party API directly from the browser often fails due to CORS restrictions, another reason to proxy through a server function.
• Not handling API errors — ask Lovable to add basic error states so a failed call doesn't silently break the UI.
• Rate limits on the provider's side causing intermittent failures that look like bugs in your app.

If the API has unusual auth (signed requests, OAuth flows) and Chat struggles, PromptSites.com can implement it directly.

Connecting an API, safely

1. Find the auth method. API key, bearer token, or OAuth. Keys and tokens must never sit in client code.
2. Store the credential as a secret. Add it through the platform so it exists only in the server runtime.
3. Call the API server-side. Write a server function that takes validated input, calls the provider, and returns only the fields your UI needs.
4. Validate input. Parse and bound everything the browser sends before it reaches the provider.
5. Handle failures loudly in logs, gently in the UI. Log the provider's status and body; show the user a readable message.
6. Cache when you can. Store results you will need again rather than calling on every render.

A prompt that produces the right shape

Add a server function that calls the API using the secret . Validate the input with a schema, return only { id, title, price }, and log the provider status and body on failure. Call it from the page with a loading and error state. Never expose the key to the browser.

Signs you have done it wrong

• The key appears in the network tab or in a client bundle
• The call works in preview but fails once published — the secret was never added to the live environment
• CORS errors in the browser — a sign the call is being made from the client instead of the server
• The provider rate-limits you — the call is inside a render or an unthrottled loop

Webhooks, the other direction

When a provider needs to call you, expose a public endpoint, verify the signature before trusting the payload, validate the body, then do the work. Never perform writes on an unverified request.

Connectors before custom code

Many popular services are available as platform connectors, which handle credentials and token refresh for you. Check for a connector before writing your own OAuth flow — it is less code, fewer secrets and no refresh logic to maintain.