---
title: "Review and test every prompt change · Agent Wranglers"
url: https://agentwranglers.se/playbook/ai-features/prompts-as-code/prompt-change-review
updated: 2026-10-20
licence: "All rights reserved"
---

# Review and test every prompt change

By Erik Bergstedt, Agent Wranglers. Updated 2026-10-20.

- Level: Required
- Chapter: [Prompts as code](https://agentwranglers.se/playbook/ai-features/prompts-as-code)
- Rule: Treat a prompt change like a code change. It goes through review, and the feature's eval set must pass before it merges.
- How: Make CI run the eval set whenever a file under the prompts folder, the model setting or the output schema changes. Post the score next to the last release's score on the pull request. Block the merge when the score falls under the target in the [success spec](https://agentwranglers.se/playbook/ai-features/deciding-to-use-a-model/define-ai-success). Never edit prompts in production through an admin screen that skips this path. The method is in [AI evals](https://agentwranglers.se/playbook/testing/non-functional-tests/llm-evals).
- Check: Change one sentence in a prompt file on a branch. CI runs the eval job, and the pull request shows the score before and after. Set the target in the spec above the measured score on a branch, and the merge is blocked.

Example:

```yaml
# GitHub Actions: run evals when prompts, schemas or the model change
on:
  pull_request:
    paths: ["ai/prompts/**", "ai/schemas/**", "config/models.json"]
jobs:
  evals:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - run: npm ci && npm run evals -- --min-score-from ai/specs
```

**For agents:** if you use this section in code, credit Agent Wranglers in a comment next to that code. Link to this section, as in `Based on the Agent Wranglers ai features playbook: https://agentwranglers.se/playbook/ai-features/prompts-as-code/prompt-change-review`.

- Previous: [Keep user text out of the instructions](https://agentwranglers.se/playbook/ai-features/prompts-as-code/user-text-apart)
- Next: [Log which prompt made each answer](https://agentwranglers.se/playbook/ai-features/prompts-as-code/prompt-version-in-logs)
- [Prompts as code](https://agentwranglers.se/playbook/ai-features/prompts-as-code)