# Agent harness and modern stack

Newer kinds of trouble: out-of-date agent instructions, old and new versions running at once after a deploy, data leaking into pages, outside services going down, rounding errors, and screens that show a change before it is saved.

- [Out-of-date agent instructions](https://atlasscope.dev/prompts/out-of-date-agent-instructions): Finds instructions that send agents to files and patterns that no longer exist.
- [Database changes during a deploy](https://atlasscope.dev/prompts/database-changes-during-a-deploy): Checks that each database change works with the old code that is still live while a release finishes.
- [Hidden data anyone can read](https://atlasscope.dev/prompts/hidden-data-anyone-can-read): Finds data sent to the browser that the screen hides but anyone can read.
- [When an outside service goes down](https://atlasscope.dev/prompts/when-an-outside-service-goes-down): Asks what happens to the app when Google, the AI Gateway or a service that sends it updates goes down.
- [Rounding and unit mix-ups](https://atlasscope.dev/prompts/rounding-and-unit-mix-ups): Finds money and percentage values that change scale or lose precision along the way.
- [Screens showing a change that was refused](https://atlasscope.dev/prompts/screens-showing-a-change-that-was-refused): Finds screens that show a change right away and keep showing it after the server refused it.

Source: https://atlasscope.dev/prompts/agent-harness-and-modern-stack