DSPy From First Principles 02: A Prompt Is Not Yet a Program

Fri, 28 Aug 2026 10:05:00 +0100

A Prompt Is Not Yet a Program

In chapter 1 we built a reasonable handwritten prompt and found the real problem: one prompt string was carrying the task semantics, role and behavioral framing, output request, and model assumptions at the same time.

The next move is not to make a more elaborate prompt. It is to decide what properties an LM component needs before we should reasonably call it a program.

DSPy From First Principles 04: Separate What From How

Fri, 28 Aug 2026 10:15:00 +0100

Separate What From How

In chapter 3 we designed a stronger contract for sentence improvement. The signature names the inputs and outputs. It says what the LM should consume and produce.

It still does not say how the LM should execute the task.

That distinction is the main subject of this chapter.

                SAME CONTRACT

input ────────> Signature ────────> output
                    │
             execution policy
              /           \
         Predict       ChainOfThought

Changing the task contract and changing the execution strategy are different operations. Treating them as the same operation is one reason prompt experiments become impossible to interpret.

Modules on Programmer.ie

DSPy From First Principles 02: A Prompt Is Not Yet a Program

A Prompt Is Not Yet a Program

DSPy From First Principles 04: Separate What From How

Separate What From How