Why Manual Test Cases Should Live in YAML

Most teams still treat manual test cases as rows in a SaaS database. That worked when cases were written slowly, reviewed rarely, and automation lived in a separate silo. It works less well now. AI can draft cases from screenshots and user stories in minutes. Automation lives next to application code. QA and dev share the same PRs. Auditors ask where test data lives and who changed what. In that world, test cases are data — and the format you choose matters as much as the tool UI. The durable direction is tests as code : plain YAML files in version control, with a thin local layer for humans to browse, run, and review. Not because databases are evil, but because git + YAML matches how we already work with code, AI, and compliance. 1. AI is good at YAML — and YAML keeps your data yours LLMs are unusually good at structured text: YAML front matter plus a Markdown body is a sweet spot. Give the model a schema ( title , tags , priority , steps, expected result) and a screenshot or user story, and you get a draft case in one pass. That matters for more than speed: Boundary cases — ask the model what you might have missed; it can reason about the scenario, not just paraphrase the story. Consistency — the same format every time makes batch generation and review predictable. The deeper point is data ownership . Cases in a vendor DB are convenient until they are not: export limits, API friction, another system to secure, another place sensitive scenarios live. Local YAML in your repo is trivial for AI to read (including Cursor, Copilot, or whatever you use next), diff, and update — without shipping your test catalog to a third party. For many teams, that is a real security and efficiency win — not ideology. 2. Manual YAML beside automation makes coverage measurable When manual cases and automated tests sit in the same repository, a few things become boring in a good way: Tag a case automated: true and point params at a Playwright or Selenium path — one file, one id. Automati