Prompt Chaining

Prompt Chaining
Break a big task into a chain of smaller prompts — where each output feeds the next.
What Is Prompt Chaining?
Prompt chaining is the technique of splitting one large, complex task into a sequence of smaller, focused prompts. The output of each step becomes the input to the next, forming a reliable pipeline instead of asking the model to do everything in a single overloaded prompt.
It is the foundation of most serious AI workflows. When a task has several distinct phases — research, structure, drafting, polishing — chaining keeps the model focused on one job at a time, which dramatically improves quality and control.
A Simple Analogy
Think of an assembly line. One station cuts, the next shapes, the next paints, the last inspects. No single worker does it all — and the product comes out cleaner because each station has one clear job. Prompt chaining is your AI assembly line.
A Classic Example Chain
Here is a four-step chain that turns a raw document into a polished piece of writing.
Extract
Gather the raw material.
Pull the key points out of a source document.
Outline
Give it structure.
Turn those key points into a logical, ordered outline.
Draft
Expand into content.
Grow the outline into a full first draft.
Polish
Refine and check.
Improve tone, tighten language, and fix any errors.
The Chain in Practice
Each step is its own prompt. Notice how the output of one is pasted into the next.
Step 1 — Extract
Extract the 5 most important points from the text below.
Return them as a short bulleted list, nothing else.
"""
[paste source document here]
"""
Step 2 — Outline
Using the key points below, create a logical outline with
a clear introduction, 3 body sections, and a conclusion.
Key points:
[paste output from Step 1]
Step 3 — Draft
Expand the outline below into a full draft.
Write in a clear, professional tone, about 400 words.
Outline:
[paste output from Step 2]
Step 4 — Polish
Polish the draft below: improve flow, remove repetition,
fix grammar, and keep it under 400 words.
Return only the final version.
Draft:
[paste output from Step 3]
Automating a Chain (Optional)
In code, a chain is simply feeding each response into the next call. Here's the idea in pseudo-JavaScript:
// Prerequisite: an API client for your chosen model
async function runChain(sourceDoc) {
const keyPoints = await ask(`Extract 5 key points:\n${sourceDoc}`);
const outline = await ask(`Create an outline:\n${keyPoints}`);
const draft = await ask(`Expand into a draft:\n${outline}`);
const finalCopy = await ask(`Polish this draft:\n${draft}`);
return finalCopy;
}
When to Chain
- The task has distinct phases (research → outline → draft → edit)
- A single prompt gives inconsistent or truncated results
- You need a checkpoint or human review between steps
- The output must pass through validation before continuing
- Different steps need different tones, formats, or tools
Single Prompt vs. Prompt Chain
| Aspect | Single Mega-Prompt | Prompt Chain |
|---|---|---|
| Reliability | Drops on complex tasks | Each step stays focused |
| Debugging | Hard to find the fault | Isolate the failing step |
| Control | All-or-nothing | Review between steps |
| Reusability | One-off | Reuse individual steps |
| Cost | Lower (one call) | Higher (multiple calls) |
Common Pitfalls to Watch Out For
Key Takeaway
Prompt chaining turns one overwhelming request into a reliable pipeline. Break the task into focused steps, pass each output to the next, and add a checkpoint where it matters — you'll get higher quality and far easier debugging.