GPT-4.1 vs GPT-4o: Which Model to Use in Production AACFlow Workflows

Which tasks should use GPT-4.1?

GPT-4.1 excels in situations where following complex, multi-step instructions precisely matters more than image understanding:

Code generation and review. GPT-4.1 scores meaningfully higher than GPT-4o on SWE-bench, the standard code editing benchmark. If your AACFlow Agent block is tasked with generating production code, reviewing pull requests, or writing test suites, GPT-4.1 is the better choice.

Data extraction from large documents. When you need to extract structured information from long PDFs, contracts, or research papers — and the full document must fit in context — GPT-4.1's 1M token window is essential. GPT-4o would require chunking, which introduces coordination overhead and potential context loss.

Multi-step orchestration prompts. GPT-4.1 handles highly detailed system prompts with many constraints and edge cases better. If your prompt defines 15 different behaviors and exception handlers, GPT-4.1 will follow them more reliably.

Long-running agentic workflows. Because GPT-4.1 can hold the full conversation history in a single context window, it is less prone to the "memory drift" that happens when context must be summarized or truncated.

Which tasks should use GPT-4o?

GPT-4o is the right choice when the workflow involves visual input or needs to handle diverse, unpredictable inputs:

Vision tasks. If your workflow processes screenshots, charts, diagrams, photos, or PDFs with embedded images, GPT-4o is the only choice among the two. GPT-4.1 is text-only.

Customer-facing chat. GPT-4o's latency profile is tuned for interactive conversations. It streams faster and handles conversational turns more naturally.

Mixed-input pipelines. When you cannot predict whether an incoming request will be text, image, or a combination, GPT-4o's unified multimodal architecture handles the variation without routing logic.

Quick summarization at moderate length. For inputs under 50k tokens that don't require images, both models perform comparably, but GPT-4o's wider community benchmarks and longer track record in production make it a safe default.

How to switch models in AACFlow

Changing the model in an AACFlow Agent block takes three clicks:

1. Open your workflow in the canvas editor and click the Agent block.
2. In the right-side configuration panel, find the Model dropdown.
3. Select gpt-4.1 or gpt-4o from the OpenAI provider group.

No API key changes are required. AACFlow uses your workspace-level OpenAI credential for all OpenAI models.

If you want to run A/B comparisons — for example, to measure accuracy differences on your specific task — use AACFlow's Evaluator block to route the same input to both models and score the outputs automatically.

A practical decision guide

Use GPT-4.1 when:

• Your workflow is code generation, review, or debugging
• Inputs exceed 50k tokens or you need 1M+ token context
• You need strict instruction-following with complex system prompts
• Cost efficiency on text-only tasks matters

Use GPT-4o when:

• Your workflow processes images, screenshots, or charts
• You are building interactive chat or customer support agents
• Your inputs are variable and may include non-text content
• You prefer the most widely tested OpenAI model in production

Both models are first-class citizens in AACFlow. The platform handles model switching, credential management, and streaming output consistently across both. The only decision is yours: pick the model that fits the task.

— Alexandr Chibilyaev