Vertex AI in Firebase is Now Firebase AI Logic: What Actually Changed

From Vertex AI in Firebase to Firebase AI Logic

If you learned Vertex AI in Firebase last year and came back in 2026 to find Firebase AI Logic, you’re not alone as I went through the same reset. I’d already shipped an Angular + Gemini demo, then spent days reconciling old blog posts, renamed Console menus, and SDK imports that no longer compiled. This article is the companion to my setup tutorial: not how to wire Angular, but what the rebrand actually means and what’s new compared to the original Vertex-only path. This is documented from the mistakes and migration work I did on a real project.

In May 2025, Firebase renamed and expanded it to Firebase AI Logic. The rename reflects a wider scope, not a different product category. Same client-side idea; more backends and features.

What's new (that wasn't in the original Vertex AI in Firebase)

1. Gemini Developer API (GoogleAIBackend)

The biggest addition. Prototype on the Spark (free) plan, then scale. Console: Build → AI Logic → Get started → Gemini Developer API. The original product only offered the enterprise Vertex/Agent Platform path.

2. Backend choice in code

Switch providers by changing initialization:

import { getAI, GoogleAIBackend, AgentPlatformBackend } from 'firebase/ai';

// Gemini Developer API — easiest way to get started (this guide uses this)
getAI(app, { backend: new GoogleAIBackend() });

// Agent Platform / enterprise (what Vertex AI in Firebase was built around)
getAI(app, { backend: new AgentPlatformBackend('global') });

You can enable both APIs in one Firebase project.

3. App Check for the Gemini Developer API

App Check can protect Developer API traffic, not just the enterprise backend. Required for production AI Logic on web; this guide wires it in Part 2.

4. New SDK module

Migrate from the deprecated path:

5. AI monitoring for client SDKs

Firebase Console dashboards now cover client-side AI Logic requests (not only server-side Genkit).

6. Unity SDK (Preview)

Client-side AI Logic for games and Android XR.

7. Image generation and editing via Gemini

Multimodal chat responses (text + image), beyond Imagen-only client access.

8. Hybrid on-device inference (web, experimental)

Gemini Nano on Chrome with prefer_on_device, falling back to cloud automatically.

9. Security upgrade (mid-2026)

Firebase AI Logic authorizes Developer API calls via a Google-managed service account, not a Gemini API key embedded in your app. Use your normal Firebase web apiKey + App Check; do not add Generative Language API to that key's allowlist (if it's still available as an option).

What was already there (unchanged by the rebrand)

• Client-side Gemini from web/mobile without your own backend
• Agent Platform / Vertex AI Gemini API (the original path)
• Firebase proxy / abuse protection
• Remote Config for changing model names without app releases
• Imagen client-side (added during the Vertex AI in Firebase era)

SDK migration snippet (if you have old code)

// BEFORE — Vertex AI in Firebase
import { getVertexAI, getGenerativeModel } from 'firebase/vertexai';
const vertexAI = getVertexAI(app);
const model = getGenerativeModel(vertexAI, { model: 'gemini-2.0-flash' });

// AFTER — Firebase AI Logic
import { getAI, getGenerativeModel, GoogleAIBackend } from 'firebase/ai';
const ai = getAI(app, { backend: new GoogleAIBackend() });
const model = getGenerativeModel(ai, { model: 'gemini-2.5-flash' });

Official references: May 2025 announcement, FAQ — why the name changed.