Prompt Engineering and Prompt Life Cycle Management

We’ve implemented a working retrieval pipeline and verified that the system retrieves relevant documentation chunks from the database.

However, retrieving relevant context doesn’t guarantee a high-quality output. If we pass retrieved chunks to the LLM with a weak instruction, such as: Here is some data, answer the question, the model's behavior becomes unpredictable.

The model may ignore the provided context, generate facts that are not present in the source text, or produce unstructured output when the application expects a well-formed response. In this lesson, we shift our focus from retrieval to generation and treat prompts as versioned, testable software artifacts rather than ad hoc text.

We will build a prompt engineering pipeline that uses:

1. Jinja2 templates to separate logic from data.

2. XML delimiters to enforce security boundaries.

3. JSON mode to ensure the output is machine-readable.

4. Git-based versioning to manage changes safely.

The architecture of a production prompt

In a prototype, you might write code like this:

In production, this is dangerous.

If the context contains a user email that looks like an instruction, the model ...