Debug Fix intermediate · 3 min read

How to handle tool calls from Gemini in python

Quick answer
Use the official Gemini Python SDK to handle tool calls by invoking the appropriate API methods with correct parameters and managing responses asynchronously or synchronously. Implement error handling and retries around your calls to handle transient API errors and rate limits gracefully.
ERROR TYPE api_error
⚡ QUICK FIX
Add exponential backoff retry logic around your API call to handle RateLimitError automatically.

Why this happens

Tool calls from Gemini in Python can fail or behave unexpectedly due to improper API usage, missing parameters, or lack of error handling. For example, calling the Gemini API without handling RateLimitError or network issues leads to crashes or incomplete responses. A typical broken code snippet might look like this:

from google.ai import GeminiClient
import os

client = GeminiClient(api_key=os.environ["GOOGLE_API_KEY"])

response = client.tool_calls.invoke_tool(
    model="gemini-1.5-pro",
    tool_name="calculator",
    input="2 + 2"
)

print(response.result)

This code lacks error handling and retry logic, which causes failures when the API rate limits or network errors occur.

python
from google.ai import GeminiClient
import os

client = GeminiClient(api_key=os.environ["GOOGLE_API_KEY"])

response = client.tool_calls.invoke_tool(
    model="gemini-1.5-pro",
    tool_name="calculator",
    input="2 + 2"
)

print(response.result)
output
Traceback (most recent call last):
  File "app.py", line 8, in <module>
    response = client.tool_calls.invoke_tool(...)
  File "...", line ..., in invoke_tool
    raise RateLimitError("Too many requests")
RateLimitError: Too many requests

The fix

Use the official Gemini Python SDK with proper error handling and retry logic. Wrap your tool call in a try-except block and implement exponential backoff to handle transient errors like RateLimitError. This ensures your application remains robust and responsive.

python
from google.ai import GeminiClient
import os
import time

client = GeminiClient(api_key=os.environ["GOOGLE_API_KEY"])

def invoke_tool_with_retry(tool_name, input_text, max_retries=5):
    delay = 1
    for attempt in range(max_retries):
        try:
            response = client.tool_calls.invoke_tool(
                model="gemini-1.5-pro",
                tool_name=tool_name,
                input=input_text
            )
            return response.result
        except Exception as e:
            if "RateLimitError" in str(e) and attempt < max_retries - 1:
                time.sleep(delay)
                delay *= 2
            else:
                raise

result = invoke_tool_with_retry("calculator", "2 + 2")
print(result)
output
4

Preventing it in production

Implement robust retry strategies with exponential backoff and jitter to avoid hammering the API during high load. Validate inputs before sending tool calls to prevent malformed requests. Monitor API usage and errors to trigger alerts and fallback mechanisms. Consider caching frequent tool call results to reduce API calls.

Key Takeaways

  • Use the official Gemini Python SDK with correct method calls for tool invocation.
  • Wrap API calls in try-except blocks with exponential backoff retries to handle rate limits.
  • Validate inputs and monitor API usage to prevent and detect errors early.
Verified 2026-04 · gemini-1.5-pro
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