Writing a Prompt: Technical Guide

Fri, 18 Apr 2025 11:02:00 +0100

I. Understanding What a Prompt Is in LangChain

In LangChain, a prompt is a textual structure designed to guide a language model. A well-constructed prompt includes several key components:

Instruction: What you explicitly ask the model to do.
Context: Additional information to frame the answer.
Input Data: The specific input provided at runtime.
Output Indicator: What kind of output is expected.

This format enables clear, framed, and reproducible queries.
Here’s another example using LangChain in Python with this structure:

Hallucinating with LangChain

Mon, 07 Apr 2025 09:22:00 +0100

I What is a hallucination?

A hallucination refers to a response generated by a language model that is factually incorrect, invented, or misinterprets reality. It can range from a minor inaccuracy to a completely fabricated citation or even a made-up technical or historical claim.

Example:

“Einstein discovered general relativity in 1975.”

That’s incorrect (it was in 1915), but the model might produce this kind of statement if it lacks the proper context or is too confident in its reasoning.

Langchain on Simple Enough Blog

Writing a Prompt: Technical Guide

I. Understanding What a Prompt Is in LangChain

Hallucinating with LangChain

I What is a hallucination?