Why is the OpenAI Assistant Analyze Image Node Truncating Long Responses?

Explanation

This issue occurs because the output from the OpenAI Assistant is getting truncated when the generated response exceeds the token limit. In other words, if the response exceeds your configured max_tokens or the conversation exceeds the maximum context length allowed by the API, the output will be cut off. The underlying API signals this with finish_reason="length".

Why It Happens

• Token Limit Exceeded: The API stops the generation once it reaches the maximum allowed tokens. Any additional text gets discarded.
• Context Length Limit: If the conversation becomes too long, parts of the text may be omitted from the response.
• No Error Message: Since this behavior is by design, you won't see an explicit error message, only the truncated output.

Potential Solutions

1. Increase Max Tokens: If possible, adjust the max_tokens parameter to allow for a longer response if the API and your plan support it.
2. Manage Context Size: Ensure the conversation doesn't grow too large by managing or summarizing previous messages, which helps maintain a shorter context.
3. Split Large Tasks: Consider breaking down the image analysis task into smaller subtasks to avoid overloading the generation process.
4. Try Different Models: Some models may have a larger context window or different token limits, so trying a model with those features might help, though you've already mentioned trying GPT-4o and GPT-4o-MINI with similar results.

Conclusion

The truncation you're observing is due to exceeding the allowed token or context limits enforced by the API. Adjusting your token settings or managing the conversation length can help mitigate this behavior. This is not a bug but rather an inherent safeguard in how the OpenAI API manages large responses.

Let me know if you need further details on how to adjust your workflow or additional configuration steps.