Tutorial

How to Add a Search Fallback When Gemini Refuses to Search

Detect Gemini google_search grounding failures and route to Scavio API as a fallback. Fixes the April 2026 empty-response bug.

Since April 2026, Gemini 2.0 Flash has an intermittent bug: google_search grounding returns empty results or refuses to trigger entirely. The March 2026 image grounding regression made it worse. Flash does not reliably invoke search, especially when external tools are also registered. This tutorial builds a detection-and-fallback layer so your agent always gets search results.

Prerequisites

  • Google AI Studio or Vertex AI credentials
  • Scavio API key
  • Python 3.8+

Walkthrough

Step 1: Call Gemini with google_search grounding

Set up the standard Gemini call with grounding enabled.

Python
import google.generativeai as genai
import os

genai.configure(api_key=os.environ['GEMINI_API_KEY'])
model = genai.GenerativeModel('gemini-2.0-flash',
    tools=[genai.Tool(google_search=genai.GoogleSearch())])

def gemini_search(query):
    response = model.generate_content(query)
    return response

Step 2: Detect empty or failed search results

Check if Gemini actually performed a search grounding call. The April 2026 bug returns candidates with no grounding metadata.

Python
def search_failed(response):
    # No grounding metadata = search did not trigger
    if not hasattr(response, 'candidates') or not response.candidates:
        return True
    candidate = response.candidates[0]
    grounding = getattr(candidate, 'grounding_metadata', None)
    if not grounding or not grounding.grounding_chunks:
        return True
    # Empty chunks = search triggered but returned nothing
    return len(grounding.grounding_chunks) == 0

Step 3: Route to Scavio on failure

When Gemini search fails, extract the query and call Scavio.

Python
import requests
H = {'x-api-key': os.environ['SCAVIO_API_KEY']}

def search_with_fallback(query):
    response = gemini_search(query)
    if search_failed(response):
        results = requests.post('https://api.scavio.dev/api/v1/search',
            headers=H,
            json={'platform': 'google', 'query': query}).json()
        return {'source': 'scavio', 'results': results}
    return {'source': 'gemini', 'response': response}

Step 4: Log failure rates for monitoring

Track how often Gemini search fails so you know when Google fixes the bug.

Python
import json, datetime

def log_search_event(query, source, failed):
    with open('search_fallback_log.jsonl', 'a') as f:
        f.write(json.dumps({
            'ts': datetime.datetime.now().isoformat(),
            'query': query, 'source': source, 'gemini_failed': failed
        }) + '\n')

Python Example

Python
import os, requests
import google.generativeai as genai

genai.configure(api_key=os.environ['GEMINI_API_KEY'])
model = genai.GenerativeModel('gemini-2.0-flash',
    tools=[genai.Tool(google_search=genai.GoogleSearch())])
H = {'x-api-key': os.environ['SCAVIO_API_KEY']}

def search(query):
    resp = model.generate_content(query)
    grounding = getattr(resp.candidates[0], 'grounding_metadata', None) if resp.candidates else None
    if not grounding or not grounding.grounding_chunks:
        return requests.post('https://api.scavio.dev/api/v1/search',
            headers=H, json={'platform': 'google', 'query': query}).json()
    return resp

JavaScript Example

JavaScript
const res = await fetch('https://api.scavio.dev/api/v1/search', {
  method: 'POST',
  headers: {'x-api-key': process.env.SCAVIO_API_KEY, 'Content-Type': 'application/json'},
  body: JSON.stringify({platform: 'google', query: userQuery})
});
const fallbackResults = await res.json();

Expected Output

JSON
Agent that always returns search results: Gemini grounding when it works, Scavio API when Gemini fails. JSONL log of failure rates for monitoring.

Related Tutorials

Frequently Asked Questions

Most developers complete this tutorial in 15 to 30 minutes. You will need a Scavio API key (free tier works) and a working Python or JavaScript environment.

Google AI Studio or Vertex AI credentials. Scavio API key. Python 3.8+. A Scavio API key gives you 500 free credits per month.

Yes. The free tier includes 500 credits per month, which is more than enough to complete this tutorial and prototype a working solution.

Scavio has a native LangChain package (langchain-scavio), an MCP server, and a plain REST API that works with any HTTP client. This tutorial uses the raw REST API, but you can adapt to your framework of choice.

Start Building

Detect Gemini google_search grounding failures and route to Scavio API as a fallback. Fixes the April 2026 empty-response bug.