Chapter 2 · Lesson 2
Build a Reusable Prompt Template
Turn a successful prompt into a maintained working tool instead of a forgotten chat message.
A weekly task works well with AI, but every person on the team prompts it differently.
Keep stable and variable parts separate
A template should preserve the decisions that stay the same while exposing the parts that change. Keep the purpose, quality rules, and output structure stable. Use clear placeholders for audience, source material, deadline, and other task-specific inputs.
Add an input checklist
Prompt quality often fails before the prompt begins because the user lacks the necessary source material. List required inputs and tell the model to flag missing information. A template that reveals an incomplete brief is more valuable than one that confidently works around it.
Treat templates as versions
Record what the template is for, who owns it, and when it was last tested. Update it when the process, tool, policy, or desired output changes. A prompt template is operational documentation, not a magic sentence.
Build the mental model
A prompt template is a small operating procedure with inputs, checks, and ownership.
Expose variables clearly
Use named placeholders rather than blank lines or comments. Every variable should say who supplies it and what a valid value looks like.
Add failure behaviour
Tell the template what to do when input is missing, contradictory, or outside scope. Stopping for clarification is often safer than producing a complete-looking draft.
A team creates a weekly portfolio update from project inputs.
Write our usual weekly portfolio report. Use the information provided and make it concise.
Inputs required: reporting period, project status, confirmed change, risk, owner, and decision needed. First list missing or conflicting inputs and stop if status or owner is absent. Then produce the approved five-field table. Version: 1.2. Owner: Operations. Last tested: 24 July 2026.
The template now defines valid input, failure behaviour, output, version, and ownership, so the team can maintain it rather than depend on memory.
How to test and version a template
Keep three test cases: a normal input, an incomplete input, and a difficult edge case. Re-run them whenever the model, process, or template changes.
Record why a revision was made. A short change note such as “v1.2: require evidence quote after two unsupported claims” is more useful than a folder of unexplained prompt variants.
Convert a successful chat into a team template
Extract the stable instructions, name every variable, and add missing-input behaviour plus one normal and one edge-case test.
Purpose: [...] Required inputs: [...] If missing: [...] Steps: [...] Output: [...] Quality checks: [...] Owner/version: [...]spot problem
What is the biggest problem with this reusable template: “Write our usual weekly report. Make it good.”?
Find the choice that creates the clearest risk or quality problem.
A template preserves a good process and makes missing inputs visible.