When designing a prompt for a complex multi-step reasoning task, where should the core instructions for Claude ideally be placed to maximize performance?
Trap 1: At the very beginning of the system prompt only.
System prompts are excellent for setting the persona and high-level rules, but for specific, data-heavy tasks, the model benefits from having task-specific instructions closer to the actual input. Relying solely on the system prompt can lead to the model losing focus when the user input becomes very long.
Trap 2: Embedded randomly within the middle of the input data.
Placing instructions in the middle of data blocks makes them harder for the model to distinguish from the content it is supposed to analyze. This leads to increased confusion and a higher likelihood that the model will treat instructions as part of the data rather than as a command.
Trap 3: In a separate API call before the main request.
Claude does not maintain state between independent API calls unless explicitly managed via a conversation history. Sending instructions in a separate call would result in the model having no knowledge of those instructions when it receives the main data in the subsequent request, causing the task to fail.
- A
At the very beginning of the system prompt only.
Why it fails: System prompts are excellent for setting the persona and high-level rules, but for specific, data-heavy tasks, the model benefits from having task-specific instructions closer to the actual input. Relying solely on the system prompt can lead to the model losing focus when the user input becomes very long.
- B
Embedded randomly within the middle of the input data.
Why it fails: Placing instructions in the middle of data blocks makes them harder for the model to distinguish from the content it is supposed to analyze. This leads to increased confusion and a higher likelihood that the model will treat instructions as part of the data rather than as a command.
- C
Directly after the XML-tagged input data in the user message.
Placing the specific task instructions after the data ensures that the model has all the necessary information loaded before it is told what to do with it. This structure aligns with how the attention mechanism processes the sequence, leading to more accurate and contextually relevant responses.
- D
In a separate API call before the main request.
Why it fails: Claude does not maintain state between independent API calls unless explicitly managed via a conversation history. Sending instructions in a separate call would result in the model having no knowledge of those instructions when it receives the main data in the subsequent request, causing the task to fail.