AuthenticationError
together_ai.errors.AuthenticationError
Stack trace
together_ai.errors.AuthenticationError: Invalid API key provided. Please check your API key and try again.
Why it happens
This error happens because the Together AI client detects that the API key used for authentication is either missing, malformed, expired, or revoked. The server rejects the request with a 401 Unauthorized status, causing the client to raise AuthenticationError.
Detection
Check for AuthenticationError exceptions when initializing or calling Together AI client methods, and log the API key environment variable presence and format before making requests.
Causes & fixes
API key environment variable is not set or is empty
Set the API key in your environment variable (e.g., TOGETHER_API_KEY) before running your application.
API key is incorrect or has a typo
Verify the API key string exactly matches the key provided by Together AI, including case and no extra spaces.
API key has expired or been revoked
Generate a new API key from the Together AI dashboard and update your environment variable accordingly.
Using the wrong environment variable name or not passing the key to the client
Ensure you pass the API key correctly to the Together AI client constructor or rely on the documented environment variable name.
Code: broken vs fixed
from together_ai import TogetherAI
client = TogetherAI(api_key='') # Passing empty or invalid key
response = client.chat('Hello') # Triggers AuthenticationErrorimport os
from together_ai import TogetherAI
os.environ['TOGETHER_API_KEY'] = 'your_valid_api_key_here' # Set your API key securely
client = TogetherAI(api_key=os.environ['TOGETHER_API_KEY'])
response = client.chat('Hello')
print(response) # Works without AuthenticationErrorWorkaround
Catch AuthenticationError exceptions and prompt the user to verify or input a valid API key at runtime, allowing fallback or retry without crashing.
Prevention
Always store API keys securely in environment variables and validate their presence and format before initializing the Together AI client to avoid authentication failures.